1.1 Introduction of the Argument

Galen states that the starting-point (ἀρχὴ) of his argument consists in the observation of the differences in actions and affections of small children. Such observation makes us realize that we are always already given a certain nature that is decisive for the state of our soul.⁹ This realization is of central importance to Galen and will conflict with what he presents as the Stoic view, namely that everyone has the potential for virtue.¹⁰ The apparent differences in those actions and affections imply a difference in capacities (δυνάμεις), which implies a difference in nature (φύσις), which Galen equates to substance (οὐσία), for nature and substance ‘refer to the same in these kinds of discussions’ (εὔδηλον δ΄ὅτι τὸ τῆς φύσεως ὄνομα κατὰ τοὺς τοιούτους λόγους ταὐτὸν σημαίνει τῷ τῆς οὐσίας).¹¹ The fact that Galen considers οὐσία and φύσις to be synonymous here is noteworthy, and will be important for our later discussion. Thus, having established on the basis of a simple empirical observation that the substances of our souls differ and having posited that ‘substance’ here refers to the same as ‘nature’, Galen will now move on to the question: what is the substance (or nature) of the soul? In this context, Galen’s use of the word οὐσία might cause some confusion, since it could either refer to a certain stuff or material, or to what something essentially is. The equation with nature and the later consideration that the substance of the soul might be immaterial make it clear that Galen must be concerned with the latter sense of οὐσία here, although, as we shall see, given Galen’s physiological perspective on the matter these two senses of οὐσία will converge to a certain extent.

Since the observation of the differences between children forms the starting-point of the argument, the answer to the question about the substance of the soul will somehow have to do justice to these observed differences in the natures of children. Thus, although we are in a sense asking about one ‘thing’, the substance or nature of the soul, this has to be something that is itself qualitatively variant to such a degree that it can account for the entire range of differences we observe in the actions and affections of small children. Given this point of departure, we can safely assume that whatever explanation of the substance or nature of the soul Galen turns out to prefer, it will have some emphasis on inherent qualitative variation.

Galen’s next step is the introduction of the tripartition familiar from PHP: there are three forms and parts (τῶν εἰδῶν τε καὶ μερῶν) of the soul, differing in kind and located in the three main organs, the liver, heart and brain. Each of these organs has its own specific substance (ἰδίαν οὐσίαν), states Galen, which seems to take us from the question of the substance of the soul to that of the substance of the three main organs.¹² The discussion of the substance of the rational part of the soul, located in the brain, is immediately related to Plato and postponed because of its particularly problematic character (it may or may not be immortal) and it will be taken up after the discussion of the substance of the other two parts:

πρῶτον οὖν ἐπισκεψώμεθα περὶ τῶν ἐν καρδίᾳ καὶ ἥπατι τῆς ψυχῆς εἰδῶν, ἅ κἀκείνῳ κἀμοὶ συνωμολόγηται φθείρεσθαι κατὰ τὸν θάνατον.¹³

Let us first, then, examine the forms of the soul in heart and liver, which are agreed by both him and me to perish at death.

tr. Singer, modified

These other two forms and parts are discussed in a kind of exchange with Aristotelian philosophy, while the discussion of the substance of the rational part of the soul will take the form of an argument against the Platonic doctrine of its immortality and non-bodily existence. Thus, Galen chose to divide his question on the substance of the soul into a discussion of the lower parts according to Aristotle, and the higher part according to Plato. Perhaps this points to a Platonist tendency, but it could also be a way to first establish Galen’s particular interpretation of Aristotelian hylomorphism, i.e. of the soul as form of the body. After all, Galen’s discussion of the rational part of the soul mostly takes the form of arguments against the Platonic doctrine of the soul’s existence as a substance separate from the body, leaving the – by then established – hylomorphic interpretation of the soul as the only alternative.

1.2 The Soul as Form of the Homoeomerous Body

In this paragraph, we shall delve further into the Aristotelian discussion of the lower two parts of the soul. Although it is only a relatively small part of the overall text, it requires quite a bit of explanation because it presupposes much from other Galenic works. Galen starts the discussion of the lower two parts of the soul with the remark that the common substance (κοινὴ οὐσία) of all bodies (!) is composed of matter and form.¹⁴ The leap from the substance and nature of the soul to the substance of all bodies is only mediated by the brief mention of the main organs, the bodily parts ‘in’ which the soul resides. The difference between the substance of the organ and the substance of the soul that resides ‘in’ the organ will, in turn, become obscured to the point of non-existence in QAM. The reason for this is not negligent arguing, however, but an underlying general theory of human nature that we find in a set of other Galenic works as well (to be discussed below). This general theory consists in a combination of Peripatetic hylomorphism and Galen’s tripartition-cum-trilocation. As we shall see below, the soul is indeed defined as something that resides ‘in’ the three main organs, but therefore not as something separable from it that does not at the same time form the substance of the organ itself (both in the sense of the ‘stuff’ and the ‘essence’ but especially in the sense of principle of movement). That is to say, the οὐσία of the soul, in the sense of what the soul is, is conflated with the οὐσία of the organ in the sense of what constitutes its nature. More specifically, the soul is located at the micro-level of our constitution, as the formal aspect of the smallest perceivable hylomorphic unit, formed by nature. Since the form of this smallest hylomorphic unit also determines the activity of the organ that exercises psychic functions, the substance of the soul and the substance within the organ seem to be identified. With regard to soul itself, this is how these two senses of οὐσία become conflated: what the soul is, is a specific mixture of qualities (i.e. form) that is always already mixed in matter. The interaction between the different qualities that make up the mixture, takes place on this micro-level. It is not perceivable with our senses itself, but causally determines the possible functions of the organs and the actions and affections of the soul, which Galen presented as the starting-point of his argument. Much of the background for this reasoning on the soul is consistent with Galen’s view on human nature as we find it in other works, but is simply presupposed or implied in QAM itself. Therefore, to understand this (Aristotelian) section of the text, we will need to have recourse to some of Galen’s earlier work, in which a more or less consistent doctrine of the constitution of human nature is developed. The relevant works are especially On the Elements according to Hippocrates (Hipp. Elem.), to which Galen refers in QAM (46,16–7 Müller), On Mixtures (Temp.), On the Natural Faculties (Nat. Fac.), On the Usefulness of the Parts (UP) and The Best Constitution of our Bodies (Opt. Corp. Const.). These texts are all dated close to each other and connected by several explicit references and programmatic resemblance.¹⁵ Galen’s commentary on the Hippocratic On the Nature of Man (HNH; the subject of Case-Study II) is also relevant, though presumably of later date, as are his various interactions with Plato´s Timaeus (the subject of Case-Study III).

In his discussion of the lower two parts of the soul in the Aristotelian section (QAM IV 773–5 K), Galen assumes with ‘Aristotle and his followers’ that the soul is the form of the body. Thus, besides his familiar Platonic-Hippocratic tripartition, he adopts, at the same time, a hylomorphic approach to the question of the nature and substance of the soul. However, he starts from the notion of a common substance (κοινὴ οὐσία) of all bodies, and explains the matter of this common substance as a kind of prima materia: it is matter without any perceivable quality, that functions (conceptually) as a receptacle for a mixture (κρᾶσις) of the four basic qualities of hotness, coldness, dryness and wetness.¹⁶ A homoeomerous body (σῶμα ὁμοιομερές) comes to be through a mixing of these four qualities in the prime matter. These homoeomerous bodies are to be distinguished from ‘organic bodies’ (ὀργανικά σώματα), which are made up of a quantity of homoeomerous bodies and form a more complex unit. Some examples of homoeomerous bodies, which Galen gives here or in other places are flesh, fat, nerve, membrane, bone, marrow and ligament.¹⁷

Now, at this point Galen does not yet conclude that the form of the body, and thus the soul, is the mixture of elemental qualities that constitutes the homoeomerous bodies:

ὥσθ’ ὅταν αὐτὸς οὗτος ᾿Αριστοτέλης εἶδος εἶναι τοῦ σώματος εἴπῃ τὴν ψυχήν, ἐρωτητέον αὐτὸν ἢ τούς γ΄ ἀπ΄ αὐτοῦ πότερον τὴν μορφὴν εἶδος εἰρῆσθαι πρὸς αὐτοῦ νοήσωμεν, ὥσπερ ἐν τοῖς ὀργανικοῖς σώμασιν, ἢ τὴν ἑτέραν ἀρχὴν τῶν φυσικῶν σωμάτων, σῶμα δημιουργοῦσαν ὅπερ ὁμοιομερές τ΄ ἐστὶ καὶ ἁπλοῦν ὡς πρὸς αἴσθησιν, οὐκ ἔχον ὀργανικὴν σύνθεσιν.¹⁸

Therefore when this Aristotle himself says that the soul is form of the body, one must ask him, or his followers, whether we should understand form here to have been used by him in the sense of shape, as in the organic bodies, or in the sense of the other principle of natural bodies, that which crafts a body that is homoeomerous and simple in terms of perception, not having organic composition.

tr. Singer, modified

Apparently, at this point in the argument, there are two options for the definition of the soul as the form of the body: the shape of organic bodies and that which ‘crafts’ the homoeomerous bodies. Also, both are considered a principle or cause (ἀρχὴ). It has been noted that the word ‘crafting’ (δημιουργοῦσαν) seems somewhat curious in this context, and that it is not clear how Galen arrives at these two options, which are introduced by him without any further explanation, as if self-evident.¹⁹ As we shall see, the necessary background for this passage can be obtained from earlier work in which Galen develops a theory of the constitution of human nature that can explain both the choice for these two options and the curious notion of ‘crafting’. The two options Galen presents refer to two different levels in the constitution of the human body. In this particular case, they refer to different levels in the constitution of the organs, since we are in the specific context of a discussion of the substance of the soul within the framework of the Platonic-Hippocratic tripartition, in which the soul is located in the three main organs. Galen takes the distinction between these two levels of composition, homoeomerous bodies and anhomoeomerous bodies (which include the organs) from Aristotle. His interpretation differs from that of Aristotle in several respects, though, and there were others using the distinction after Aristotle, to whom Galen sometimes responds.²⁰ However, both share the basic notion that the homoeomerous bodies are made up of a mixture of the four elemental qualities (or of the elements that are in turn made up of the elemental qualities and their matter) and form the basic building blocks of the more complex parts of our body, called anhomoeomerous parts, examples of which are the hand, the arm, the brain, liver, and other such parts or organs. These more elementary substances are called ‘homoeomerous’ because the mixing of the four qualities in the primary matter takes place in such a thorough manner that it is impossible to actually (as opposed to conceptually) separate them again from each other, so that every part taken from such a particular body would be exactly like any other to our perception.²¹ The larger corporeal units, which are formed by the homoeomerous substances in turn, are called anhomoeomerous, because they consist of different homoeomerous parts that can be separated when we analyse the anhomoeomerous part. Thus, at the lowest compositional level, there is the prime matter in which the four qualities are mixed to form a homoeomerous unity. Specific to man (and other sanguineous animals), is that the four qualities form the four humours when they are mixed, and that men’s homoeomerous substances are thus made out of the four humours.²² In portraying this general compositional picture, Galen does not consistently include the humours – as opposed to the homoeomerous and organical bodies – but from the passages where he does their position in the overall scheme seems clear.²³ The basis of four elemental qualities and prime matter applies not just to human beings but to everything in the cosmos: everything is eventually formed through the mixing of these four qualities in the prime matter.²⁴ This is why Galen could take such a general definition of the substance of all bodies (the κοινή οὐσία) as his point of departure: at the micro-level, all beings can be described and analysed in the same basic terms (although in different constellations, of course, which results in all the differences we observe). This is important for several reasons. First of all, it constitutes the unity of the cosmos and man’s kinship with the rest of creation (especially in the absence of an identifiable creator-god). Second, it seems to imply that an analysis of the nature and substance of the human soul does not require a fundamentally different approach than the analysis of any other being in the cosmos, since all beings, including man, are made up of the same kind of hylomorphic combination. Thus, the introduction of such a notion of a κοινή οὐσία right at the start of the discussion of the substance or nature of the soul betrays that, for Galen, there is not necessarily anything metaphysical about the analysis of the οὐσία of the soul. That is to say, the soul may perhaps not be of a fundamentally different nature than the other things and beings in the cosmos. When Galen further on in QAM relates the dryness of an intelligent soul to the dryness of the stars (see below), he can do so because of this basic doctrine of a κοινή οὐσία of all bodies.

The distinction between ‘homoeomerous bodies’ and ‘organic bodies’ employed by Galen in QAM is hierarchically the same as the difference between homoeomerous and anhomoeomerous bodies. In the context of QAM, where the substance of the soul is under consideration from the perspective of the tripartition related to the three main organs, the compositional level of the anhomoeomerous bodies is restricted to organs. This means that the second candidate for the form of the body, or the soul, the ‘other cause’ that ‘crafts’ a body that is homoeomerous and simple, must be (the mixing interaction of) the four elemental qualities. Again, this kind of cause is not unique to human beings but common to all bodies in the cosmos:

΄ἀλλ΄ ἡμεῖς γε πρῶτον μὲν ἐκ τῶν αἰτίων, οἷς ἅπαντα διοικεῖται τὰ κατὰ τὰς φυσεις, τοῦ θερμοῦ λέγω καὶ ψυχροῦ καὶ ξηροῦ καὶ ὑγροῦ, δεύτερον δ΄ ἐξ αὐτῶν τῶν ἐναργῶς φαινομένων κατὰ τὸ σῶμα ψυχρὸν καὶ ξηρὸν εἶναί τινα χρῆναι χυμὸν ἀπεδείξαμεν.²⁵

But we have demonstrated, firstly from the causes by which everything throughout nature is governed, that is to say from the warm and the cold and the dry and the moist, and secondly, from obvious bodily phenomena, that there must be a cold and dry humour.

tr. Brock, modified

Galen considers the elemental qualities as the governing causes of all beings, since they, in their mutual interaction, decide the form (literally) that the smallest elements of those beings take. Therefore, in UP, Galen states that the mixture of qualities constitutes the specific substance (ἰδία οὐσία) of the homoeomerous bodies.²⁶ We have observed above how Galen mentioned the ἰδία οὐσία of the organs in QAM. What constitutes the specific substance of the homoeomerous body is the mixture of its qualities and what constitutes the specific substance of an organ is its homoeomerous bodies.²⁷ There is a kind of causal hierarchy here, according to which the more elemental level decides what the more complex level is, that is to say, in which the οὐσία in terms of the component stuff, determines the οὐσία in terms of ‘what something is’.

As Galen proceeds to explain in the passage in UP, the nature of a part (i.e. a homoemerous body in this context) is determined by the specific state of its elemental qualities. The smallest bodies in turn determine the specific form of the larger ones, and thus also the specific functions and activities of these larger bodies.²⁸ The ἑτέρα ἀρχὴ referred to in QAM, which forms a homoeomerous body that does not yet have organic composition and that is identified by Galen as soul, refers to the mixture of the elemental qualities. At this point one may ask, as Socrates in the Phaedo, whether there should not be something governing this mixing itself, something steering and perhaps intelligent.²⁹ The question seems to come down to this one: what exactly is the ‘demiurge’ doing the crafting here? After all, it seems difficult to account for the notion of a teleologically structured cosmos, and perhaps particularly for something as complex as the human soul, on the basis of a random gathering of elemental qualities. This is indeed a crucial point for Galen, as is well known, since the answer to this question makes the difference between his doctrine and forms of what he considers to be random material determinism (represented by atomists for example), which are always firmly rejected by him. But we shall return to this point below, at the very end of this paragraph. First, let us summarize what we have found so far. We have two levels of composition: the formation of the homoeomerous substances through the mixture of the four elemental qualities and the construction of anhomoeomerous substances through the combination of several homoeomerous substances (sometimes Galen differentiates between more basic and complex organs as well, the complex ones being made up of a combination of basic ones, see the citation below). If we consider man more specifically, we might add the formation of the four humours as a compositional phase between the four elemental qualities and the homoeomerous substances. When Galen asks about the substance or nature of the soul from his specific hylo-morphic and tripartitional perspective, two possible answers are presented, corresponding to these two general levels of composition, each functioning as a cause at its respective level. The brief and somewhat enigmatic discussion in QAM presupposes a doctrine of the human constitution from the prime matter to the whole, summarized in Hipp. Elem. as follows:

ἐκ μὲν γὰρ τῶν χυμῶν τούτων ἕκαστον τῶν ὁμοιομερῶν ἐγένετο, συνιόντων δὲ τούτων ἀλλήλοις ἀποτελεῖται τὸ πρῶτόν τε καὶ ἁπλούστατον ὄργανον, ὅ μιᾶς ἐνεργείας ἕνεκεν ὑπὸ τῆς φύσεως ἐγένετο. τούτων δὲ αὖθις ἀλλήλοις συντιθεμένων ἕτερον ὄργανον καὶ μεῖζον γεννᾶται, κἀκείων αὐθις ἀλλήλοις ἐπιπλεκομένων ἡ τοῦ παντὸς ἀποτελεῖται σύμπηξις.³⁰

Each of the homoeomerous parts came to be from these humours, and when they are conjoined with each other they produce the first and simplest organ, which was brought into being by nature for the sake of a single activity. When these [organs] are combined with each other in turn, another, larger organ is produced, and when these [larger organs] are joined with each other again, the structure of the whole is completed.

tr. De Lacy, modified

Galen adopts an hierarchical structure, in which the more complex level is produced from, or even by the more simple level. In this way, the structure of the whole seems, in the end, to a large extent determined by the way the elemental qualities interact at the most basic level and form or alter the homoeomerous parts. In HNH, Galen relates this causal hierarchy to his discussion of the soul in QAM:

ἐπεὶ τοίνυν καὶ τὸ αἷμα αὐτὸ δεῖται τῶν τεσσάρων ποιοτήτων, ὑγρότητος καὶ ξηρότητος καὶ θεμότητος καὶ ψυχρότητος, εὔδηλον ὅτι καὶ τῆς τῶν ἄλλων χυμῶν δεήσεται μίξεως· καὶ διὰ τοῦτο τὸ εὐκρατότατον αἷμα μεθέξει τι καὶ φλέγματος καὶ χολῆς ξανθῆς καὶ μελαίνης. ἔστι δὲ καὶ ἕτερος τις λόγος φυσικὸς οὐ σμικρὰν ἔχων πιθανότητα, καθ΄ ὅν εἰς ἠθῶν ἐπιτηδείων γένεσιν οἱ τέσσαρες ἀποδείκνυνται χυμοὶ χρήσιμοι. προαποδεῖξαι δὲ χρὴ πάλιν ἐν αὐτῷ ταῖς τοῦ σώματος κράσεσιν ἑπόμενα τὰ τῆς ψυχῆς ἤθη, περὶ οὗ καὶ ἡμῖν ἑτέρωωθι γέγραπται.³¹

But since, then, blood too itself requires the four qualities (wet, dry, hot and cold), it is clear that it will also require a mixture of the other humours. So for this reason the most well-tempered blood will have a share to some extent of phlegm, and of yellow and black bile. There is also another physical account which has no little plausibility, according to which the four humours are proved to be effective in the generation of the states of character which are appropriate to them. In it we first need to establish that the states of character of the soul are consequent upon the mixtures of the body, about which we have written elsewhere.

tr. Hankinson

The qualities mix to form humours, the basic building blocks of the constitution of man, and the humours, in turn, are instrumental in the formation of character traits, which follow upon the specific mixture formed by the qualities. Thus, in this passage, with reference to QAM, we notice how the more simple level of physical composition does not only determine the more complex level of physical composition, but also the ‘psychic’ category of character.

In On the Natural Faculties (Nat. Fac.) Galen also elaborates on the two phases of composition, describing how both come to be through different capacities of nature:

ἀλλ΄ ἡ μὲν γένεσις οὐχ ἁπλῆ τις ἐνέργεια τῆς φύσεως, ἀλλ΄ ἐξ ἀλλοιώσεώς τε καὶ διαπλάσεώς ἐστι σύνθετος. ἵνα μὲν γὰρ ὀστοῦν γένηται καὶ νεῦρον καὶ φλὲψ καὶ τῶν ἄλλων ἕκαστον, ἀλλοιοῦσθαι χρὴ τὴν ὑποβεβλημένην οὐσίαν, ἐξ ἧς γίγνεται τὸ ζῷον· ἵνα δὲ καὶ σχῆμα τὸ δέον καὶ θέσιν καὶ κοιλότητάς τινας καὶ ἀποφύσεις καὶ συμφύσεις καὶ τἀλλα τὰ τοιαῦτα κτήσεται, διαπλάττεσθαι χρὴ τὴν ἀλλοιουμένην οὐσίαν, ἥν δὴ καὶ ὕλην τοῦ ζῴου καλῶν …³²

Generation, however, is not a simple activity of Nature, but is compounded of alteration and of shaping. That is to say, in order that bone, nerve, veins, and all other parts may come into being, the underlying substance from which the animal comes to be must be altered; and in order that the substance so altered (which we also call the material of the animal) may acquire its appropriate shape and position, its cavities, outgrowths, attachments, and so forth, it needs to be shaped.

tr. Brock, modified

These two capacities of nature involved in the genesis of beings correspond to the two compositional phases of homoeomerous and anhomoeomerous parts. The homoeomerous substances, such as bone, nerve and veins, come to be because of a mixing of the qualities in an underlying substance and subsequently require the right shape and position within the body, as well as the proper connections to other parts. The first stage is conceived as a capacity of nature described as generative and alterative:

ὀστοῦν δὴ καὶ χόνδρον καὶ νεῦρον καὶ ὑμένα καὶ σύνδεσμον καὶ φλέβα καὶ πάνθ΄ ὅσα τοιαῦτα κατὰ τὴν πρώτην τοῦ ζῴου γένεσιν ἡ φύσις ἀπεργάζεται δυνάμει χρωμένη καθόλου μὲν εἰπεῖν τῇ γεννητικῇ τε καὶ ἀλλοιωτικῇ, κατὰ μέρος δὲ θερμαντικῇ τε καὶ ψυκτικῇ καὶ ξηραντικῇ καὶ ὑγραντικῇ καὶ ταῖς ἐκ τῆς τούτων κράσεως γενομέναις …³³

Now Nature constructs bone, cartilage, nerve, membrane, ligament, vein, and so forth, at the first stage of the animal’s generation, using a power which is, in general terms, generative and alterative, and, in more detail, warming, chilling, drying, or moistening; or such as spring from the blending of these …

tr. Brock, modified

Notably, Galen adds that the particular flesh (ἡ ἰδία σὰρξ) of the organs, such as the liver and the heart, as well as the particular body of the brain (καὶ τοῦ ἐγκεφάλου τὸ ἴδιον σῶμα) are also of this kind. Thus, we can deduct from this passage that the three main organs, which are the seats of the soul, are made up of homoeomerous bodies generated by nature’s mixing of the elemental qualities. This substance, explains Galen, is something entirely peculiar to the specific organ.³⁴

The second phase, the construction of anhomoeomerous bodies through the combination of homoeomerous ones, is effected by the ‘shaping’ capacity:

τὴν δὲ σύνθεσιν αὐτῶν καὶ τὴν τῶν ἐμφυομένων πλοκὴν καὶ τὴν εἰς τὸ ἔντερον ἔκφυσιν καὶ τὴν τῆς ἔνδον κοιλότητος ἰδέαν καὶ τἆλλ΄ ὅσα τοιαῦτα δύναμις τις ἑτέρα διέπλασεν, ἥν διαπλαστικὴν ὀνομάζομεν, ἥν δὴ καὶ τεχνικὴν εἶναι λέγομεν …³⁵

… while the bringing of these together, the combination therewith of the structures which are inserted into them, the outgrowth into the intestine, the shape of the inner cavities, and the like, have all been determined by a power which we call the shaping or formative power; this power we also state to be artistic …

tr. Brock, modified

The shaping power puts the homoeomerous parts together in such a manner that complex beings capable of exercising particular functions arise. This is the power Galen praises throughout UP and which will be known in later tradition as the ‘plastic faculty’ (διαπλαστικὴ).

Galen describes both of these phases of generation as capacities of the same nature. Since this nature is wise, that is to say, since it operates according to an observable systematic teleology, the exercise of these two respective capacities would logically require a sufficient extent of coordination. The exercise of the first capacity must already anticipate the second.³⁶ In QAM, both of these capacities of nature, are considered as causes for the formation of the human body. Through the first, nature manifests itself as cause of the generation of homoeomerous bodies, through the second, as cause of the shaping of organs and their interconnections.

But why, we may ask, is Galen so preoccupied with elaborating such a hierarchy of parts of our body? This is because he assumes that the simplest parts of our body hold the key to the question of our nature. Here we have to bring to mind a passage from the beginning of Hipp. Elem.:

… ἀλλὰ τὰ πρῶτά τε καὶ ἁπλούστατα τῇ φύσει καὶ μηκέτ’ εἰς ἄλλα διαλυθῆναι δυνάμενα ζητῶμεν, εἰ μέλλοιμεν ἢ ἀνθρώπου φύσεως ἤ τινος ἄλλου τῶν ὄντων ἐπιστήμην ἀκριβῆ λήψεσθαι.³⁷

… but let us find the parts that are first and simplest by nature and that are no longer capable of being dissolved into other parts, if we are to obtain precise knowledge of the nature of man or any other being.

tr. De Lacy, slightly modified

Apparently, Galen assumes that knowledge of the nature of any being can only be obtained by analysis of its smallest parts. Therefore, an investigation into the nature of man, or whatever other entity, would have to take the form of a structural analysis of its component parts.³⁸ This becomes particularly relevant when we remember the identification of nature and substance in QAM referred to earlier: Galen stated that the words nature and substance mean the same in ‘these kind of discussions’ (τοὺς τοιούτους λόγους).³⁹ That is to say, given this apparent basic presupposition, one would expect the question for the nature or substance of the human soul in QAM to also take the direction of an analysis of the smallest elements of man’s constitution, and in fact, given the hylomorphic outline: of an analysis of the formal aspect of the most elemental body. And as we shall see, that is exactly the direction Galen takes, identifying as the substance of the soul the second of the two presented options, namely the mixture of elemental qualities that generates homoeomerous bodies.

1.3 The Homoeomerous Bodies as Primarily Active

Basically, Galen’s question now is whether we should look for the soul on a macro- or a more micro-level of the formal organisation of our bodies. When we bear the quoted passage from Hipp. Elem. in mind, it is not surprising that Galen’s choice falls on the micro-level. The answer to the question of the nature or substance of a being must be sought in its smallest parts, after all. He adds, however:

ἀποκρινοῦνται γὰρ ἐξ ἀνάγκης τὴν ἑτέραν ἀρχὴν τῶν φυσικῶν σωμάτων, εἴ γε δὴ τούτων εἰσὶ πρώτως ἐνέργειαι (δέδεικται γὰρ τοῦθ΄ ἡμῖν ἑτέρωθι καὶ νῦν, ἂν δεήσῃ, πάλιν εἰρήσεται).⁴⁰

For they [Aristotle and his followers] have to answer, necessarily, that it [the form of the soul] is the other principle of the natural bodies – since, indeed, to these the activities primarily belong (this has been shown by us elsewhere, and will be stated again now, if you require).

tr. Singer, modified

Galen’s justification for the choice in favour of the micro-level of our composition is that the ‘activities’ primarily belong to this level. What does this mean? It may seem striking that the activity of our soul would primarily take place at the level of the elemental mixture that forms the homoeomerous body. In fact, it seems even more striking from an Aristotelian perspective, since it is stated in Aristotle’s work that the homoeomerous parts are for the sake of the anhomoeomerous ones exactly because actions and functions belong to the latter.⁴¹ Again, Galen is presupposing a lot of his own doctrine, and he now simply states that he has already explained this elsewhere. Singer notes that there is a parallel for the notion that the activities primarily belong to the homoeomerous bodies in Loc. Aff., where the same compositional hierarchy of man’s constitution appears as well, and where we find references to QAM.⁴² Unfortunately, however, the explanation remains missing there also, although it is clear that in this context Galen is speaking about the powers of the rational soul. The passage is about affections of the rational soul that damage the power of reasoning and memory. These affections are caused by a humoral imbalance (i.e. finally by an imbalance of the elemental qualities), which affects the homoeomerous parts of the brain, which ‘primarily act’. In this passage, Galen explains affections of the rational soul, such as lethargy, in terms of the homoeomerous bodies of the brain being affected by too much coldness or wetness.

There is another useful passage in this regard in Nat. Fac., in the same context as the quotations above on the generative and shaping powers of nature. In this passage, Galen explains how each animal has as many alterative powers (ἀλλοιωτικὰς δυνάμεις) and particular activities (τὰς ἐνεργείας ἰδίας) as it has elemental parts (στοιχειώδη μόρια).⁴³ He says this in the context of a discussion of homoeomerous parts, and it is clear from the preceding text that these elemental parts must refer to homoeomerous parts (also defined as αἰσθητὰ στοιχεῖα).⁴⁴ Therefore, what he seems to imply here, as well as in the passages from QAM and Loc. Aff. discussed above, is that each of the homoeomerous parts exercises a particular function in a primary fashion, so that, for example, the activities of the brain, which are the activities of the rational part of the soul, are each primarily exercised by particular homoeomerous bodies in the organ of the brain.

We find more evidence of this privileged role of the homoeomerous bodies when it comes to the substance and activities of our functions in other works as well. In Opt. Corp. Const., Galen asks what the best constitution of our bodies is. He refers to Hipp. Elem. and Temp., and presupposes the theoretical framework which he has developed there.⁴⁵ The question turns out to be whether the micro-level of the composition of homoeomerous bodies or rather the macro-level of organic composition is responsible for the optimal constitution. In the end, the answer is that both are indispensable. As in QAM, both levels of composition are considered to be causes for our functioning, though not in exactly the same manner:

ἡ μὲν γὰρ ἐκ θερμοῦ καὶ ψυχροῦ καὶ ξηροῦ καὶ ὑγροῦ σύμμετρος κρᾶσις ὑγίεια τῶν ὁμοιομερῶν ἐστι τοῦ σώματος ἡμῶν· ἡ δ’ ἐκ τούτων ἁπάντων τοῦ ζῴου διάπλασις ἐν θέσει καὶ μεγέθει καὶ σχήματι καὶ ἀριθμῷ τῶν συνθέτων ὑπάρχει …⁴⁶

For a healthy state of our body consists in a well proportioned mixture of the homoeomerous parts out of the hot, cold, dry, and wet, but the shaping of the animal from all of these [parts] consists in the position, magnitude, configuration and number of the component elements.

Clearly, the second level of composition is described in quantitative and spatial terms. Once the homoeomerous parts themselves are constituted through a specific mixture of the various qualities, at the second compositional level it is about how these parts relate to each other in terms of position, magnitude, configuration and number.⁴⁷ In UP, these characteristics of the second stage of composition are called accidental, as opposed to the mixture of the elemental qualities, which forms the substance and nature of any part (αὗται γὰρ τὴν ἰδίαν οὐσίαν τῶν μορίων συμπληροῦσιν).⁴⁸ First, Galen mentions how there are secondary qualities such as smell and color, which follow upon (ἕπονται) the nature of the homoeomerous bodies (which nature properly consists in the mixture of the four elemental qualities). Then, he adds that other things also result or follow of necessity (ἕτερα δ΄ἐξ ἀνάγκης συμβέβηκε), namely position, magnitude, structure and shape (θέσις καὶ μέγεθος καὶ πλοκὴ καὶ διάπλασις). Both of these categories are distinguished from that of the mixture that constitutes the homoeomerous bodies, as secondary features that follow upon the mixture itself.⁴⁹ A few lines further, he describes how, when one wants to determine the usefulness of a body part, one needs to first look at its particular activity, which is in most cases derived from its peculiar substance (ἰδία οὐσία). This clearly refers back to the mixture of the homoeomerous parts. Then, one needs to see whether the part is useful because of the activity (διὰ τὴν ἐνέργειαν) or because of something that follows upon the mixtures (διὰ τι τῶν ἐπομένων ταῖς κράσεσιν). Again, the implication is that the activity belongs primarily to the mixture itself. Finally, one needs to look at each of the accidental attributes (ἕκαστον τῶν συμβεβηκότων), which Galen again specifies as position, size, structure and shape.

All of this corresponds to what Galen does in QAM, where he refers to the particular substance of each of the organs in which the soul resides (ἔχοντος δ’ ἰδίαν οὐσίαν ἑκατέρου τῶν σπλάγχνων). The elemental qualities make up the substance and nature of a part (e.g. one of the organs in which the soul resides) and determine its activities. We find the same idea in another passage from Opt. Corp. Const., where Galen asks about the substance (οὐσία) of the body when it is functioning at its best. He refers to Hipp. Elem., Temp. and UP and gives a similar distinction between organs and their constituent parts with regard to activities, as the one we saw above:

ἀρχὴ δὲ κἀνταῦθα τῆς εὑρέσεως, εἰ ζητήσαιμεν, ὅπως διακειμένου τοῦ σώματος ἐνεργοῦμεν ἄριστα. χρὴ τοίνυν εἰς τοῦτο τῶν ἤδη δεδειγμένων ἐν ἑτέροις ὑπομνήμασιν ἀναμνησθῆναι, πρῶτον μὲν ὡς ἐκ θερμοῦ καὶ ψυχροῦ καὶ ξηροῦ καὶ ὑγροῦ τὰ σώμαθ΄ ἡμῶν κέκραται· δέδεικται δὲ περὶ τούτων ἐν τῷ Περὶ τῶν καθ΄῾Ιπποκράτην στοιχείων γράμματι· δεύτερον δὲ τοῦ διορίσασθαι τὰς κράσεις τῶν μορίων· εἴρηται δὲ καὶ περὶ τούτων ἐν τοῖς Περὶ κράσεων ὑπομνήμασιν· ἐφεξῆς δὲ τούτων, ὡς ἕκαστον μὲν τῶν ὀργανικῶν τοῦ σώματος μελῶν ἕν ἔχει τῶν ἐν ἑαυτῷ μορίων αἴτιον τῆς ἐνεργείας, τὰ δ΄ἄλλα σύμπαντα τὰ συμπληροῦντατὸ πᾶν ὄργανον ἐκείνου χάριν ἐγένετο.⁵⁰

And here the starting-point of our enquiry must be the investigation as to what is the constitution of the body at the time when our functioning is at its best. Now at this point we must make reference to matters which have been demonstrated previously in other works. First, that our bodies are a mixture of hot, cold, dry and wet. This was shown in our treatise on The elements according to Hippocrates. Secondly, that one must distinguish between the mixtures of different parts – as discussed in our work on Mixtures. The next point is that each of the organic parts of the body has one cause of activity from the parts that it has in itself; and everything else that goes to make up that organ as a whole comes into being in accordance with that purpose.

tr. Singer, modified

The cause of activity from the parts within the organ must refer to the homoeomerous bodies. We cannot assume that each organ as a whole has one activity – that would not make sense as most organs have many different activities according to Galen. So what must be meant here is, again, that each of the activities of the organ has a single cause deriving from the homoeomerous bodies the organ has within itself. Thus, this cause of activity, located ‘in’ the organs, is not a separate immaterial substance of any kind but rather the formal aspect of the most elemental level of composition, namely, the specific mixture of elemental qualities that forms the homoeomerous part, which is said to be primarily active.⁵¹

It is at this micro-level of composition that qualitative change is generated and the conditions for the activities of the soul, such as perception, are created, because Galen views the elemental qualities as a kind of primary agents of activity and change:

΄ὥστ’, εἰ μὲν τὰς πρώτας τε καὶ στοιχειώδεις ἀλλοιωτικὰς δυνάμεις ζητοίης, ὑγρότης ἐστὶ καὶ ξηρότης καὶ ψυχρότης καὶ θερμότης· εἰ δὲ τὰς ἐκ τῆς τούτων κράσεως γενομένας, τοσαῦται καθ’ ἕκαστον ἔσονται ζῷον, ὅσαπερ ἂν αὐτοῦ τὰ αἰσθητὰ στοιχεῖα ὑπάρχῃ· καλεῖται δ’ αἰσθητὰ στοιχεῖα τὰ ὁμοιομερῆ πάντα τοῦ σώματος μόρια …⁵²

Therefore, if you wish to inquire into which alterative powers are primary and elementary, these are moisture, dryness, coldness, and warmth, and if you wish to inquire into the things that arise from the mixture of these, there will be so many of these in each animal as it has perceptible elements. The name perceptible elements is given to all the homoeomerous parts of the body.

tr. Brock, modified

The qualities are described here as δυνάμεις in the primary sense, the primary and elementary forces of change. They act upon each other and constitute an interactive relation of mutual change that is the fundamental condition for all human functions. Another passage in which this notion comes to the fore can be found in The Therapeutic Method (MM), again in combination with the notion that each homoeomerous part exercises one activity:

καὶ τοίνυν ἐπειδὴ τῶν τοῦ ζῴου μορίων ἕκαστον ἰδίαν ἐνέργειαν ἐνεργεῖ, τῶν ἄλλων ἐνεργειῶν εἰς τοσοῦτον διαφέρουσαν εἰς ὅσον καὶ αὐτὸ διαφέρει τῶν ἐνεργούντων αὐτάς, διαφέρει δὲ τῷ θερμότερον, ἢ ψυχροότερον, ἢ ὑγρότερον, ἢ ξηρότερον ὑπάρχειν, ἢ κατὰ συζυγίαν τι τούτων πεπονθέναι, τὴν κρᾶσιν αὐτῶν φυλακτέον ἐστὶ τῷ τὴν ἐνέργειαν φυλάττοντι.⁵³

Therefore, when each of the parts of the organism performs a particular activity, which differs from other activities to the extent that the part itself differs from those parts that perform those activities – that is, differs by being hotter, colder, moister, or drier, or by being affected in terms of a conjunction of these [qualities] – you must preserve their activity by preserving their mixture.

tr. Johnston and Horsley, modified

The parts Galen is referring to here are, again, homoeomerous parts, as is clear from the immediate context. Shortly before this passage, he states that he shall return to the discussion of the disease that befalls the homoeomerous parts, ‘to which the activities of the living being primarily belong’ (ὧν πρῶτόν εἰσιν αἱ κατὰ τὸ ζῷον ἐνέργειαι).⁵⁴ The activity of a given homoeomerous part of the body differs from the activity of other parts to the extent that the substances of these parts respectively differ, that is to say, to the extent that they differ in their mixture of the four elemental qualities. Again, we find that the at first surprising choice for the homoeomerous bodies as location of the soul in QAM, based on the seemingly vague remark that ‘the activities primarily belong there’, has an extensive basis in Galen’s other works.

Galen grounds the very possibility of activity in this most fundamental level. In Hipp. Elem., he emphasizes that qualitative difference is a necessary condition for the functions of the soul, indeed for the very existence of the soul. There, he argues that perception can only arise in a body if we assume that the four elemental qualities that make up the body are ‘changed and mixed and altered through and through’ (μεταβαλλόντων τε καὶ κεραννυμένων καὶ ἀλλοιουμένων δι΄ ὅλων).⁵⁵ If this interaction of various qualities at the most microscopic level would not take place, there would be a completely static situation, change and difference (such as there is between all the various beings) would not be possible and therefore none of the capacities of the soul could exist. This is closely related to one of the objections Galen habitually makes against the atomists: if they assume only one kind of basic substance, they cannot explain perception and pain, because these are processes that assume qualitative difference. This qualitative difference is provided when we assume these four different elemental qualities that can interact with each other and change their substance.⁵⁶

The dependence of all parts of the body on the mixture of the elementary qualities also becomes manifest in the case of the activities being damaged. If the mixture is of a bad quality, the organs are not able to perform their basic activities, while, if they are of good quality, their activities are performed well:

διὰ γὰρ τὴν ἐκ τῶν τεττάρων ποιὰν κρᾶσιν ἑκάστου τῶν μορίων ὡδί πως ἐνεργοῦντος ἀνάγκη πᾶσα καὶ διὰ τὴν βλάβην αὐτῶν ἢ διαφθείρεσθαι τελέως ἢ εμποδίζεσθαί γε τὴν ἐνέργειαν καὶ οὕτω νοσεῖν τὸ ζῷον ἢ ὅλον ἢ κατὰ τὰ μόρια.⁵⁷

For, since each part functions such as it does because of the specific mixture of the four [qualities], it is absolutely necessary that through damage of these qualities the activity is either completely destroyed or at least impeded, and that this is how the animal becomes sick either as a whole or with respect to certain parts.

All activities of living beings are eventually dependent on the mixture of the elemental qualities that form their most basic components. The capacities of the parts that exercise our functions and activities are decided on this micro-level, because that is where quality resides. Galen is quite clear that this goes for every part of the human body that fulfils any particular function:

ἐμοὶ μὲν οὖν καὶ ἡ φλὲψ καὶ τῶν ἄλλων ἁπάντων ἕκαστον διὰ τὴν ἐκ τῶν τεττάρων ποιὰν κρᾶσιν ὡδί πως ἐνεργεῖν δοκεῖ.⁵⁸

Thus, it seems to me that the vein, and each of all the other [parts] as well, functions such as it does because of the specific mixture of the four [elemental qualities].

Again, ‘each of all the other parts’ must include the three main organs in which the three parts of the soul reside and that are also made up of mixtures. That is to say, the functioning of the liver, heart and brain, ‘in’ which the respective parts of the soul reside, is determined by the specific mixture of its component homoeomerous parts, which are primarily active.

Another interesting passage in this regard can be found in the discussion of melancholy in Loc. Aff. book III, chapters 9 and 10.⁵⁹ In the ninth chapter, Galen states that it ‘appears reasonable’ (εὔλογον ἐφαίνετο) to him, that the soul itself (τὴν μὲν ψυχὴν αὐτὴν) resides in the body of the brain (ἐν τῷ σώματι τοῦ ἐγκεφάλου κατῳκῆσθαι), where thinking and memory is located.⁶⁰ In the tenth chapter, when he discusses melancholy of the brain, he differentiates between the brain being affected by the black bile as an organic part (ὡς ὀργανικῷ μορίῳ) and it being affected as a homoeomerous part (ὡς ὁμοιομερεῖ). Then he presents the thesis of QAM, both the one presented in its title, and the stronger one of the soul actually being a mixture:

ἐπεὶ γὰρ ἤτοι κρᾶσίς ἐστιν ἡ ψυχὴ τῶν δραστικῶν ποιοτήτων, ἢ ὑπὸ τῆς κράσεως αὐτῶν ἀλλοιοῦται, τὴν μὲν ὡς ὀργανικῷ μορίῳ τῷ ἐγκεφάλῳ λυμαινομένην χολὴν ἐπὶ τὸ σῶμα τετράφθαι φησι τοῦ ἐγκεφάλου, γίγνεται δὲ τοῦτο κατὰ τὰς ἐμφράξεις· τὴν δ΄ ὡς ὁμοιομερεῖ τὴν κρᾶσιν ἀδικοῦσαν ἐπὶ τὴν διάνοιαν.⁶¹

Since the soul either is a mixture of the active qualities, or is altered by the mixture of these qualities, he [Hippocrates] says that the bile damaging the brain as an organic part affects the body of the brain, and this happens through stoppages; but the bile that damages the mixture as a homoeomerous part, affects the mind.

The relation with QAM is clear, and at the end of chapter 10 Galen makes it explicit himself, saying that in that particular work he has demonstrated (ἐμοί ἀποδέδεικται) that the humours and generally the mixture of the body alters the activity of the soul. And here the division between organic and homoeomerous parts of the brain corresponds to the division of the body of the brain and the mind respectively. When the brain is damaged as a homoeomerous part, the rational soul itself (διάνοια) is affected, whereas, when the brain is affected as an organic part, the body of the brain is affected. Therefore, again, when Galen says in QAM that the soul resides in the organ, there is no need for us to assume that he is referring to anything other than the formal aspect of the homoeomerous parts of the brain, which are inside the organ.

In another passage earlier in Loc. Aff., Galen distinguishes two views on the soul and its relation to the body: some of the philosophers say that the soul is in its surrounding body as we are in a house; others say that the soul is the form of the body and as such inseparable from it. Galen, as often, is not too explicit on his preferences, but it is clear from this passage that he finds the latter view more appealing because it is better able to explain why the rational capacities are altered when the substance of the brain is altered.⁶² After all, what he proceeds to do in the following book of Loc. Aff., is to show how various affections of the rational soul, such as lethargy, phrenitis or melancholy, are caused by alterations in the mixture of the brain in terms of the humours and elemental qualities (or by alterations in another body part, in the case of an affection through sympathy). Likewise, at the beginning of QAM, Galen states that the philosophers did not properly understand the notion of capacity (δύναμις) in their discussions of the substance of the soul, since they apparently thought that these capacities are some kind of objects inhabiting their substances in the same way we inhabit houses.⁶³

We can see, now, how the capacities of the soul depend on the mixture of the body in the most fundamental sense possible, according to Galen: the kind of activity a living being can exercise is determined by the way the elemental qualities interact and form its homoeomerous bodies; these homoeomerous bodies exercise the activities in a primary sense and are, in turn, part of the organs as the locations from where these functions are exercised.

Now that we know why the activity must primarily (πρώτως) belong to the level of the homoeomerous bodies, we can take our findings back to the argument of QAM. It is now much easier, I hope, to understand why Galen concludes that the soul as form of the body must be identified with the mixtures of elemental qualities, since these are the causes of the capacities, functions or activities of a specific living being.

1.4 The Substance of the Soul as Mixture

After Galen decides that soul, as form of the body, must be located at the level of the homoeomerous bodies because these are primarily active, he concludes the following:

καὶ μὴν εἴπερ ἐξ ὕλης τε καὶ εἴδους ἅπαντα συνέστηκε τὰ τοιαῦτα σώματα, δοκεῖ δ’ αὐτῷ τῷ ᾿Αριστοτέλει τῶν τεττάρων ποιοτήτων ἐγγιγνομένων τῇ ὕλῇ τὸ φυσικὸν γίγνεσθαι σῶμα, τὴν ἐκ τούτων κρᾶσιν ἀναγκαῖον αὐτοῦ τίθεσθαι τὸ εἶδος, ὥστε πως καὶ ἡ τῆς ψυχῆς οὐσία κρᾶσίς τις ἔσται τῶν τεττάρων …⁶⁴

And surely if all such bodies are composed of matter and form, but according to Aristotle himself the natural body comes to be because the four qualities come to be in the matter, it is necessary to posit the mixture of these as the form of it, so that the substance of the soul too will somehow be some mixture of the four …

Thus, through the hierarchical schema of the various levels of our constitution, his notion of the homoeomerous bodies as primarily acting and the linking of the parts of the soul to the main organs, Galen has now integrated Aristotelian hylomorphism into the Platonic-Hippocratic tripartition-trilocation he posited as axiomatic from the outset.⁶⁵ The soul is the form of the body in the sense of a mixture of elemental qualities that comes to be in a prime matter and forms homoeomerous bodies that are primarily active and reside in the larger compositions that are the three main organs. The different soul parts reside in these organs, that is to say: as the formal aspect of a hylomorphic unity, they make up the micro-level of their constitution that is the primary cause of their specific activity. As we have seen, this notion of soul is prepared in other writings of Galen. Thus, it seems as if Galen, in QAM, actually did display that audacity needed to make statements on the substance of the soul which he referred to in his Causes of Symptoms (Caus. Symp).⁶⁶ In any case, as we shall see below, further on in QAM he does not only applaud the Peripatetic Andronicus for defining the substance of the soul as a mixture, but also praises him for his audacity.⁶⁷

Now, besides being audacious (for reasons that involve more than the overcoming of a sceptical or agnostic attitude, as will become clear below), this may also seem like a rather strong conclusion: the substance of the soul, the cause of our actions and affections, is nothing more than a particular mixture of the four elementary qualities? Is this not an extremely ‘physicalist’ position? And does this not amount to some kind of determinism, without room for free will?⁶⁸ Indeed, many scholars have found it difficult to accept this conclusion as Galen’s own, and have developed interpretations of QAM that weaken its status (see below, paragraph 3).

So far we have left out two important general points, however, which, I think, add nuance and complexity to Galen’s position. First, there is the question of the ‘demiurge’ of the mixture, which we briefly alluded to above. Even if it is the case that the specific mixture of the elemental qualities makes up the substance of the soul and therefore all capacities, affections and activities of the soul are dependent on this mixture, the exact ramifications of this view are utterly unclear as long as it remains unspecified what the specific formation of the mixture itself is dependent upon. Galen has some answers to this question of the ‘demiurge’ of the mixture and we shall treat those at the end of this paragraph. Secondly, we have to qualify the extent of Galen’s conclusion in the Aristotelian section in the following two ways. First, as in the example of small children at the beginning of QAM, we seem to be still in the context of an early or compositional phase of the body. As we saw in the quotation above, Galen states that ‘the natural body comes to be because the four qualities come to be in the matter’. In other words, at least when it comes to this passage in QAM, it is clear from the text that the focus here is on the initial formation of the soul through the mixture. As we shall see below (paragraph 4), we can differentiate between an initial and natural formation of the mixture that accounts for the children’s differences in natural character, and a later formative causality that springs from the rational part of the soul and that is apparently supposed to complete this initial formation. This brings us to the second qualification: this entire discussion (at this point in the text) still pertains only to the lower two of the three forms or parts of the soul. As we have seen, right before the beginning of the Aristotelian section, Galen remarked that Plato considered the rational form of the soul to be immortal, whereas he himself is unable to take position in the matter.⁶⁹ This remark structured the discussion that followed, for it led to the division into the Aristotelian section on the lower two parts and the Platonic section on the rational part of the soul. Galen returns to this division between the mortal parts and (possibly immortal) rational part of the soul only after the Aristotelian section, which must mean that the conclusion proposed there, that the substance of the soul must be some mixture of the four elemental qualities, is not valid at this point for the rational part of the soul. Indeed, when Galen takes up the discussion of the rational part of the soul, he does so by asking whether it too (i.e. as the lower two parts) can be considered a particular mixture.⁷⁰ As we shall see, Galen will eventually accept the same conclusion for the rational part of the soul as well, but in a more tentative and careful manner and not without some preliminary discussion, which conveys the exceptional position of the rational part with regard to the mixture. For now, it is sufficient to remember that Galen has postponed the discussion of the rational part of the soul, and that it takes place in the context of a discussion of the views not of Aristotle, but of Plato.

With these two general points in mind – the unanswered question of the ‘demiurge’ of the mixture and the restricted extent of Galen’s conclusion so far – we must observe three things with regard to this conclusion. First, nowhere in the remaining text of QAM does Galen distance himself from the conclusion that the οὐσία of the soul is a mixture of the four elemental qualities. Second, in several places the conclusion is almost literally repeated, exactly as if Galen takes it as proven within his own text.⁷¹ Finally, we have already noticed that Galen, right after the Aristotelian section, wonders if the rational part of the soul can be considered a particular mixture as well, that is to say, in the same way as the other two parts are a mixture.

A closer look at this sentence – from the section that we have referred to as the Platonic section (775–782 K) – also shows the close connection for Galen between the thesis that the substance of the soul is a mixture and the central thesis he presented at the beginning of QAM, that the capacities of the soul follow the mixtures of the body:

εἰ μὲν οὖν λογιζόμενον εἶδος τῆς ψυχῆς ἐστι θνητὸν, ἔσται καὶ αὐτὸ κρᾶσίς τις ἐγκεφάλου καὶ πάνθ’ οὕτως τὰ τῆς ψυχῆς εἴδη τε καὶ μέρη τὰς δυνάμεις ἑπομένας ἕξει τῇ κράσει· τουτέστιν αὐτὴ οὖν ἡ τῆς ψυχῆς οὐσία …⁷²

If, then, the rational form of the soul is mortal, it too will be a particular mixture, [namely] of the brain, and thus all the forms and parts of the soul will have their capacities dependent on the mixture – that is, on the substance of the soul.

tr. Singer, slightly modified

First of all, the substance of the soul is again equated with the mixture here, but this time it is suggested (for the first time) that this equation may be valid for all parts of the soul. The conclusion presented here in hypothetical form is the same as the one Galen approvingly ascribes to Andronicus right after the Platonic section in which he argues against the immortality and incorporeal existence of (the rational part of) the soul (see below). The structure of the text here is telling. Schematically, it has the following form: argument for the substance of the lower two parts of the soul being a mixture of the elemental qualities; introduction of a dilemma concerning the rational part: it is either mortal, and then it too (and thus the entire soul) will be a particular mixture, or it is separate and immortal, as the Platonists argue; arguments against one leg of the dilemma, i.e. the Platonic doctrine that the soul is a separate, immortal substance; introduction (and approval) of Andronicus’ position that the substance of the whole soul is a mixture. This is particularly noteworthy because it has been argued that Galen, in the passage in which he introduces Andronicus’ view, would merely be spelling out the consequences of an Aristotelian position, rather than giving his own doctrine on the substance of the soul.⁷³ What is more, he says that if it is the case that the rational form of the soul is also (καὶ, again, like the other two parts of the soul) a mixture, the central thesis of QAM – that the capacities of the soul are dependent on the mixture – is proven. If the rational part can also be shown to be a mixture, the central thesis has been proven for the entire soul. That shows the direct connection for Galen between the notion that the substance of the soul is a mixture of elemental qualities and the central thesis.⁷⁴ In other words: to show that the substance of the soul is a mixture of elemental qualities is considered by Galen to be conducive to proving QAM’s main thesis that the capacities of the soul follow or depend upon the mixtures of the body.⁷⁵ And that makes sense, considering the general way in which Galen defines the relation between substance and capacity in the passage before his discussion of the various parts of the soul (IV 769–771 K). We have briefly alluded to this above. It is a point that many of the philosophers do not understand correctly, according to Galen: they conceive of a capacity as some kind of object inhabiting a substance. Instead, Galen explains, a capacity is nothing but an appellation given in relation to a certain activity, which is also why we say that a substance necessarily has as many capacities as activities (we can only ascribe to a substance a capacity after it (or perhaps a being of similar nature) has exercised the activity that we can subsequently recognize it is capable of).⁷⁶ The agent of those activities is the substance (οὐσία) itself, as Galen’s example of aloe makes clear. In retrospect the substance could be said to ‘have’ the capacity for doing that which it does, which merely expresses the relation between the cause, i.e. the substance, and its (observed) effect:

… καὶ διὰ τοῦτο τοσαύτας δυνάμεις ἔχειν τὴν οὐσίαν φαμέν, ὅσας ἐνεργείας, οἷον τὴν ἀλόην καθαρτικήν τε δύναμιν ἔχειν καὶ τονωτικὴν στομάχου καὶ τραυμάτων ἐναιμων κολλητικὴν ⟨καὶ⟩ ἰσοπέδων ἑλκῶν ἐπουλωτικὴν ⟨καὶ⟩ ὑγρότητος βλεφάρων ξηραντικήν, οὐ δήπου τῶν εἰρημένων ἔργων ἕκαστον ἄλλου τινὸς ποιοῦντος παρ΄αὐτὴν τὴν ἀλόην. αὕτη γάρ ἐστιν ἡ ταῦτα δρῶσα, καὶ διὰ τὸ δύνασθαι ποιεῖν αὐτὰ τοσαύτας ἐλέχθη δυνάμεις ἔχειν, ὅσα τὰ ἔργα.⁷⁷

… and therefore we say that the substance has as many capacities as activities; for example that aloe has a capacity of cleansing and toning the mouth of the stomach, of agglutinating bleeding wounds, of cicatrizing grazes, and of drying the wetness of the eyelids – without there being some other thing that performs each of these actions apart from the aloe itself. For it is the aloe that does these things; and it is because it can do these things that it is said of it that it has these ‘capacities’, as many as the actions.

tr. Singer, slightly modified

The substance, being the aloe, is itself active and does things. Therefore, we say that it has the capacity to do those things, recognizing that it can do the things it does. That does not mean that there is some thing that the aloe has besides the substance that it is, it is just a way of saying that this substance can do what we observe it doing. It is also clear from the example of the aloe that a single substance could have several capacities. Galen states that we could say the same thing about the rational soul ‘which is seated in the brain’. Once we recognize that it is a substance that is primarily active and that does things, and that we attribute ‘capacities’ to this substance on the basis of its activity, it becomes evident that proving that the substance of the soul is a mixture of elemental qualities is more than conducive to proving the thesis that the capacities of the soul are dependent on the mixture of the body. This could be the very reason that Galen is so much more explicit on the substance of the soul here than in his other work – i.e. this notion of the substance of the soul serves his purpose of proving the central thesis of QAM. However, I think that we should be careful not to brush aside his account of the substance of the soul being a mixture as a mere tool to prove the main thesis expressed in the title, especially not since, as we have seen, it is coherent with some of his earlier writings. In any case, such an approach would also be reasoning in the wrong direction. I consider it both more fruitful and more elegant to employ the opposite perspective: Galen argues for the main thesis of QAM because he has what he thinks are good arguments for it, and one of those arguments is that it is plausible that the substance of the soul is actually a mixture of elemental qualities.

Finally, after the Platonic section (IV 775–782 K), Galen rhetorically asks whether it is not obvious that the mortal part of the soul is in every way a slave to the body, if even the rational part changes along with the mixture of the body, as he has just shown, and then repeats the earlier conclusion once more:

ἄμεινον δὲ φάναι μὴ δουλεύειν ἀλλ΄ αὐτὸ δὴ τοῦτ΄ εἶναι τὸ θνητὸν τῆς ψυχῆς, τὴν κρᾶσιν τοῦ σώματος, ἐδείχθη γὰρ ἔμπροσθεν ἡ θνητὴ ψυχὴ κρᾶσις οὖσα τοῦ σώματος.⁷⁸

It is even better to state that the mortal part of the soul is not ‘a slave to’, but that it actually is precisely this, i.e. the mixture of the body, for it has been shown above that the mortal soul is a mixture of the body.

tr. Singer, modified

This is a very explicit repetition of the conclusion reached in the Aristotelian section.

It is also an important passage because here Galen makes a clear distinction between the notion that the soul is merely dependent on or follows (i.e. is a slave to) the mixture of the body on the one hand, and the notion that the soul actually is the mixture on the other, and then proceeds to express his preference for the latter option.

At this point in the text Galen is ready to take the next step, and to commit himself to the view that the substance of the entire soul is nothing but a mixture of elemental qualities, which he introduces as the view of Andronicus the Peripatetic. We shall get to that passage below, after we have delved into the preceding discussion of the rational part of the soul, which takes place, as we have noted, in a Platonic context.

1.5 Soul and Nature

For now, what remains to be discussed in this paragraph, is the role of the ‘demiurge’ of the mixture. If the mixture is the substance of the soul and therefore causes the affections and activities of the soul, then we have to wonder what is responsible for the formation of the mixture itself. We have noticed that Galen, in QAM, seems to attribute a ‘demiurgic’ or crafting activity to the elemental qualities. He does so in the following passage in Hipp. Elem. as well:

εἴπερ οὖν αὗται μὲν ἴδιαί τινων ὑπάρχουσι ζῷων, αἱ δὲ τὴν ὅλην οὐσίαν ἀλλοιοῦσαί τε καὶ μεταβάλλουσαι πρῶταί τέ εἰσι τῇ φύσει καὶ κοιναὶ πάντων τῶν ὄντων καὶ τῶν στοιχείων δημιουργοί, δῆλον, ὡς ὑγρότης καὶ ξηρότης καὶ θερμότης καὶ ψυχρότης ἑκάστου τῶν ὄντων συνιστῶσι τὴν οὐσίαν.⁷⁹

Thus, if these [qualities] are peculiar to some animals, but those that alter and change the whole substance are primary in nature and common to all beings and crafters of the elements, it is clear that wetness, dryness, hotness and coldness form the substance of every being.

tr. De Lacy, modified

He also does so, here:

αὗται γὰρ μόναι τὴν ὑποκειμένην οὐσίαν ἀλλοιοῦσαι τὴς τε εἰς ἄλληλα μεταβολῆς τῶν στοιχείων εἰσὶν αἴτιαι καὶ φυτῶν καὶ ζῴων δημιουργοί.⁸⁰

… for they [the four elemental qualities] alone, by altering the underlying substance, are causes of the change of the elements into each other and crafters of plants and living beings.

tr. De Lacy, modified

We notice how the elemental qualities (primary in nature and common to all beings) are not only presented as the agents of change and constituents of the substance of all beings, but are also called δημιουργοί. In fact they are singled out as the only causes and crafters. What are we to make of this? It seems confusing, because we know that Galen often refers to ‘nature’ as the creator of man. In fact, the entire UP is presented as a work to prove the ingeniousness and wisdom of the demiurgic activity of nature. What this must imply, if we are to make any coherent sense of Galen’s texts (and we can), is that nature is the ‘demiurge’ in a primary sense, mixing the elemental qualities in accordance with some intelligent plan that already presumes the ensouled being in its final state, while the elemental qualities also fulfil a role as crafters, but in a secondary sense, i.e. according to the plan of nature, as its instruments as it were. Such an interpretation would fit Galen’s teleological outlook as he presents it at the beginning of UP:

΄οὕτω μὲν σοφώτατον τῶν ζώων ὁ ᾄνθρωπος, οὕτω δὲ καὶ χεῖρες ὄργανα πρέποντα ζώῳ σοφῷ. οὐ γὰρ ὅτι χεῖρας ἔσχε, διὰ τοῦτο σοφώτατον, ὡς ᾿Αναξαγόρας ἔλεγεν, ἀλλ’ ὅτι σοφώτατον ἦν, διὰ τοῦτο χεῖρας ἔσχεν, ὡς ᾿Αριστοτέλης φησὶν, ὀρθότατα γινώσκων.⁸¹

Thus man is the most intelligent of living beings, and so, also, hands are the instruments suitable for an intelligent living being. For it is not because he has hands that man is the most intelligent, as Anaxagoras says, but rather it is because he is the most intelligent that he has hands, as Aristotle says, judging most correctly.

tr. May, slightly modified

In this reading, the natural teleology of functions would predetermine the mixture of elemental qualities, which, in turn, generates anhomoeomerous parts such as the hand. The elemental qualities themselves then may be called ‘δημιουργοί’, but only in a derivative sense. Indeed, they function as a causa efficiens with regard to the activities of the anhomoeomerous organ or body-part and with regard to the activities of the soul. However, they have their own causa efficiens as well, which operates with skill and wisdom and which ensures that the activity of the qualities is not random, because this cause is intelligent somehow.⁸² Such a distinction between a primary and derivative sense of the efficient cause has parallels in Galen’s work:

΄πρὸς μὲν οὖν τὸ πρῶτον κινοῦν, ὅπερ ἐστὶ τὸ ἡγεμονικὸν, ὀργάνου λόγον οἱ μύες ἔχουσι, πρὸς δὲ τὸ κινούμενον ὀστοῦν ὑφ’ ἑαυτῶν καὶ τοῦτον μὲν, ἀλλὰ καὶ τὸν τοῦ δημιουργοῦ.⁸³

Thus, with respect to that which moves first, which is the leading [part of the soul], the muscles have the status of instrument, but with respect to the bone moved by them, they have both the status of instrument and that of “demiurge”.

The meaning here is obvious: the muscles are an instrument (ὄργανον) in relation to the rational part of the soul that moves them, but they are a ‘demiurge’ or efficient cause in relation to the bones, since they effectively move the bones. This passage on the muscles, with the use of the same word δημιουργός, provides a good analogy for the sense in which nature and the elemental qualities can both be considered δημιουργοί. In relation to nature as creator of everything, the elemental qualities are an instrument because they are mixed according to nature’s systematic teleology. In relation to any more complex structure or activity that they effectively cause to be, they are δημιουργοί. In fact, we actually have another passage where the elemental qualities are called instruments (ὄργανα) in the same sense as the muscles above, and nature is designated as the true formative power:

… κατὰ δεύτερον δὲ τρόπον, ὅτι τῆς διαπλαστικῆς ἐν τῇ φύσει δυνάμεως οὐ μέμνηνται τεχνικῆς τ΄ οὔσης καὶ τοῖς τῆς ψυχῆς ἤθεσιν ἀκολούθως διαπλαττούσης τὰ μόρια. περὶ ταύτης γάρ τοι καὶ ὁ ᾿Αριστοτέλης ἠπόρησε, μή ποτ΄ ἄρα θειοτέρας τινὸς ἀρχῆς εἴη καὶ οὐ κατὰ τὸ θερμὸν καὶ ψυχρὸν καὶ ξηρὸν καὶ ὑγρόν. οὔκουν ὀρθῶς μοι δοκοῦσι ποιεῖν οἱ προπετῶς οὕτως ὑπὲρ τῶν μεγίστων ἀποφαινόμενοι καὶ ταῖς ποιότησι μόναις ἀναφέροντες τὴν διάπλασιν. εὔλογον γὰρ ὄργανα μὲν εἶναι ταύτας, τὸ διαπλάττον δ΄ἕτερον.⁸⁴

… but also in a second way, in that they do not make mention of the shaping capacity in nature, which is craftsmanlike, and which shapes the parts consequently upon the character traits of the soul. Regarding this capacity, indeed, even Aristotle raised the question whether it might, in fact, be from some more divine source, rather than in accord with the hot, the cold, the dry and the wet. Therefore it seems to me wrong when people make rash assertions on the greatest of issues, attributing the shaping to the qualities alone. For it is reasonable to suppose that these latter are the instruments by which it takes place, while that which does the actual shaping is something else.

tr. Singer and van der Eijk, slightly modified

This shaping or formative power in a primary sense is nature, or Nature with a capital ‘N’, a divine cause. From this primary perspective, the elemental qualities and their mixture are instruments, even though they function as (efficient) cause when they are related to the more complex structures or actions they form or cause, just like the muscles are instruments in relation to the brain and causes in relation to the moving of the bones.

It makes sense to interpret the demiurgic dimension of the mixture of elemental qualities in this way since, for Galen, there must be an intelligent cause behind this mixture that can account for the wonderful teleological order of the cosmos:

΄ὡς ἔτυχε δὲ περιπλεκόμενα, σπανίως μέν ποτε χρήσιμον ἐργάζεται τὸ δημιούργημα, πολλάκις δ’ ἄχρηστόν τε καὶ μάταιον. αὕτη τοιγαροῦν αἰτία τοῦ μὴ βούλεσθαι τὴν φύσιν εἶναι τεχνικὴν ἐκείνους τοὺς ἄνδρας, ὅσοι τὰ πρῶτα σώματα τοιαῦτα εἶναι φασιν, οἷά περ οἱ τὰς ἀτόμους εἰσάγοντες λέγουσιν.⁸⁵

But when they are interwoven in a random fashion, they rarely ever produce a useful work, rather often something useless and futile. This is exactly the reason why those men do not want nature to be skilful, I mean those that say that the primary bodies are such as those that propose the atoms say.

So, we could say the specific mixture of elementary qualities forms the substance of the lower two parts of the soul, and these substances are themselves formed by nature, i.e., a divine, wise and skilful power. But, does this not imply that the lower two parts of the soul are only effective causes in the derivative sense as well? What is primarily active in the lower parts of our soul, particularly in the desiderative or vegetative part seated in the liver, is nature. Therefore, in a way nature is eventually the true agent of the movement of which these parts are said to be the origin in a derivative sense. One beautiful consequence (if you like) of this line of thinking is that, because Galen considers nature itself as something divine and because it turns out to be the true effective cause of the actions and affections of our lower soul-parts, the actions and affections of our lower soul-parts – provided they have the right or ‘natural’ measure, of course – can be considered ‘natural’ in the sense of being divinely motivated much rather than random. We should keep in mind that the soul that is under discussion here, is something that is very closely associated, for Galen, to the rest of creation, and not something peculiar to human beings. In the sixth book of PHP for example, when Galen undertakes his investigation of the desiderative part of the soul, or the powers residing in the liver, he starts from an analysis of plants. This is because the power that is under investigation (τὴν ζητουμένην δύναμιν) is present there by itself and thus easier to analyse.⁸⁶ The crucial thing to grasp here is that it is the same power that is under investigation, whether we analyse the desiderative power of plants or the human soul, because it is eventually the power of nature and it does not ‘belong’ to an individual being in the sense that we might now be inclined to think of the soul of a specific person (this might be different for the higher part of the soul, of course). Likewise, in Foet. Form., Galen suggests that ‘enquiry into the formation of plants’ could be used to ‘learn exactly what needs the [human] embryo has during the period in which it is still managed by one soul in the same way as plants are’.⁸⁷ We can see here how difficult it can be in Galen to disentangle ‘soul’ from ‘nature’: this (vegetative) part of the soul can even simply be termed ‘nature’, he says, as the followers of Chrysippus apparently term it, whereas Aristotle and Plato preferred the word soul.⁸⁸ In UP, too, Galen decides to simply leave aside the question of whether this part of the soul should be called ‘nature or nutritive soul’, and in Nat. Fac. he states that it is only a matter of convention to call the nutritive capacity either ‘natural’ or ‘psychic’.⁸⁹

And even though we have seen that, in QAM, the role of nature is primarily associated with the context of the generation of a living being, we can learn from Nat. Fac. that the powers of nature that are manifested in the elemental mixture of the lower soul parts remain in function to guarantee the sustenance of these beings too:

εἰ μὴ γὰρ δύναμις τις σύμφυτος ἑκαστῳ τῶν ὀργάνων ὑπὸ τῆς φύσεως εὐθὺς ἐξ ἀρχῆς δοθείη, διαρκεῖν οὐ δυνήσεται τὰ ζῷα, μὴ ὅτι τοσοῦτον ἀριθμὸν ἐτῶν ἀλλ΄ οὐδ΄ ἡμερῶν ὀλιγίστων …⁹⁰

If there were not an inborn power given to each of the organs by nature immediately at the beginning, the animals would not be able to last even for a few days, let alone for so many years as they actually do.

tr. Brock, modified

Thus, nature is not only creator, but also maintainer. To a certain extent, at least, the functions of living beings, including functions that we would perhaps be inclined to think of as psychic, can be understood as capacities of nature:

κατὰ δὲ τὴν προτέραν εἰρημένην αἵρεσιν οὐχ ὑστέρα τῶν σωμάτων ἡ φύσις, ἀλλὰ πολὺ προτέρα τε καὶ πρεσβυτέρα. καὶ τοίνυν κατὰ μὲν τούτους αὕτη τὰ σώματα τῶν τε φυτῶν καὶ τῶν ζῴων συνίστησι δυνάμεις τινὰς ἔχουσα τὰς μὲν ἑλκτικάς θ΄ ἅμα καὶ ὁμοιωτικὰς τῶν οἰκείων, τὰς δ΄ ἀποκριτικὰς τῶν ἀλλοτρίων, καὶ τεχνικῶς ἅπαντα διαπλάττει τε γεννῶσα καὶ προνοεῖται τῶν γεννωμένων ἑτέραις αὖθίς τισι δυνάμεσι, στερκτικῇ μέν τινι καὶ προνοητικῇ τῶν ἐγγόνων, κοινωνικῇ δὲ καὶ φιλικῇ τῶν ὁμογενῶν.⁹¹

According to the first-mentioned teaching, on the other hand, Nature is not posterior to the bodies, but is a long way prior to them and older than they are; and therefore in their view it is Nature that puts together the bodies of both plants and animals; and this she does by virtue of certain capacities which she possesses – these being, on the one hand, attractive and assimilative of what is appropriate, and, on the other, expulsive of what is foreign. Further, she skilfully moulds everything during the stage of genesis; and she also provides for the creatures after birth, employing here other capacities again, namely, one of affection and forethought for offspring, and one of sociability and friendship for kindred.

tr. Brock, modified

According to this view (to which Galen subscribes), nature, the skilful and wise artisan, does not leave its creatures alone after their generation. We can see here how Galen explains some basic emotional functions, such as affection for others, as a natural capacity. This seems to involve the part of the soul seated in the heart, although Galen is much less inclined to conflate this soul-part with nature as he is with the part in the liver. In general, I think that we would do well to understand Galen’s nature not as an external creator that makes autonomous beings other than itself, but as ‘something’ more immanent that is itself present in the living beings and continues to work its capacities in them, as the guardian of life:

ἀνεπιτρόπευτα γὰρ ἐάσαντες αὐτὰ καὶ τέχνης καὶ προνοίας ἔρημα μόναις ταῖς τῶν ὑλῶν οἰακιζόμενα ῥοπαῖς, οὐδαμοῦ δυνάμεως οὐδεμιᾶς τῆς μὲν ἑλκούσης τὸ προσῆκον ἑαυτῇ, τῆς δ΄ ἀπωθούσης τὸ ἀλλότριον, τῆς δ΄ ἀλλοιούσῆς τε καὶ προσφυούσης τὸ θρέψον, οὐκ οἶδ΄ ὅπως οὐκ ἂν εἴημεν καταγέλαστοι περί τε τῶν φυσικῶν ἐνεργειῶν διαλεγόμενοι καὶ πολὺ μᾶλλον ἔτι περὶ τῶν ψυχικῶν καὶ συμπάσης γε τῆς ζωῆς.⁹²

For if it were conceded that they [the living beings] are without guardianship, devoid of artistry and foresight, governed only by the rule of matter and not by any power such as the attracting of what is appropriate to itself, the rejecting of what is foreign, the alteration and assimilation of that which shall nourish it, then I am sure we would make fools of ourselves discussing natural activities, and even more so discussing psychical activities and, in fact, life as a whole.

It would be ridiculous to even discuss the activity of the soul without assuming that nature, in the form of the natural capacities that are innate in every living being, fulfils a governing and guarding function. We can take that quite literally, since the activities that are described here (and repeated throughout Nat. Fac.) as the activities of nature, are no different than the activities of the lowest part of the soul. Again, we notice that, at least when it comes to the parts of the soul that man shares with other living beings, and particularly the vegetative or desiderative soul seated in the liver, there is nothing about it that hinders an analysis in the same physical terms as the rest of creation. This is another way in which we need to modify the conclusion of the Aristotelian section in QAM, namely that the substance of the soul is a mixture: the conclusion applies only to the lower two soul parts, which are in general considered to be the same as the souls of plants and animals and can to a large extent be understood as the workings of nature itself. This nature, furthermore, is intelligent. That is to say, it works according to a systematic teleology, including in its most primary activities of cooling, drying, heating and moistening.

1.6 Conclusion

To conclude this first paragraph and summarize the results of our analysis, we can extract the following views from the first part of QAM and the earlier work on which it relies.

The substance of the lower parts of the soul is a mixture of the elemental qualities. This mixture is the formal aspect of the smallest component parts (i.e. the homoeomerous bodies) of their respective organs (liver and heart). It is the cause of the (psychic) functions exercised from these organs. This substance itself is formed, and to a large extent also governed by nature. Therefore, nature, in a strict sense, is the cause of those functions and that which is primarily active when these functions are exercised. However, since nature is conceived as skilful and wise, this governance should not be understood as a random determination of functions that we would otherwise understand as being in the control of individual beings, but rather as the manifestation of a divine and beautiful teleological order that is as it should be.

Yet, there is something within this order that makes things more complex, because it shares some of the governing skill of nature without completely coinciding with it. This has been left out of consideration so far. We shall now turn to the next passage in QAM, after the Aristotelian section discussed above, where Galen takes up the postponed discussion of the rational part of the soul. It will turn out that Galen partly explains this highest part of the soul, the only part that is peculiar to human beings (among mortal beings, that is), in the same terms as the other two parts. Galen argues that its substance is a mixture of elemental qualities as well. However, he also attributes to the rational part a rather exceptional status: it shares something with its maker.

2.1 The Substance of the Rational Soul as Mixture

As we have seen, Galen considers the central thesis of QAM proven if it can be shown that the rational part of the soul is mortal and identical to the mixture that constitutes the brain, the highest of the three main organs. This conflicts with the doctrine of contemporary Platonists, who tend to view the rational part of the soul as immortal and capable of existing separately from the body. Thus, what Galen has to do from here on (775–782 K) to prove the proposed thesis, is to prove the impossibility of the immortality and separate existence of the soul. He gives various arguments to this end, most of them in some way showing the dependence of the state of the soul on the body and thus discrediting the idea of the soul’s independent existence. The example of wine, for instance, is recurrent in showing how, upon consumption of it, the capacities of the soul are immediately affected by the change in the bodily mixture.

Galen proceeds to show that the hot, cold, dry and wet, so all four of the elementary qualities that make up the mixture of the brain, each modify the capacities of the rational soul and can even cause death or – as the Platonists would have it – the separation from the body. Now, it is important to note that Galen, by arguing against the immortality and separate existence of the rational part of the soul, i.e. against its independence of a specific bodily constitution, is actually arguing in favour of it being a mixture of the brain. This becomes clear from the disjunction he presents at the outset of the Platonic section:

εἰ μὲν οὖν τὸ λογιζόμενον εἶδος τῆς ψυχῆς ἐστι θνητὸν, ἔσται καὶ αὐτὸ κρᾶσις τις ἐγκεφάλου· καὶ πάνθ΄ οὕτω τὰ τῆς ψυχῆς εἴδη τε καὶ μέρη τὰς δυνάμεις ἑπομένας ἕξει τῇ κράσει, τουτέστιν τῇ τῆς ψυχῆς οὐσίᾳ· εἰ δ΄ ἀθάνατον ἔσται, ὡς ὁ Πλάτων βούλεται, διὰ τί χωρίζεται ψυχθέντος σφοδρῶς ἢ ὑπερθερμανθέντος ἢ ὑπερξερανθέντος ἢ ὑπερυγρανθέντος τοῦ ἐγκεφάλου, καλῶς ἂν ἐπεποιήκει γράψας αὐτὸς ὥσπερ καὶ τἆλλα τὰ κατὰ ταύτην ἔγραψε.⁹³

Thus if the reasoning form of the soul is mortal, it too will be a particular mixture, [namely] of the brain, and then all the forms and parts of the soul will have their capacities dependent on the mixture – that is, on the substance of the soul; but if it turns out to be immortal, as Plato would have it, he would have done well to explain in writing himself why it is separated when the brain is excessively cooled, heated, dried or moistened, as he wrote about the other matters concerning it [i.e. the soul].

tr. Singer, modified

Clearly, we have a dilemmatic structure here: the rational part of the soul is either mortal or immortal. If it is mortal, it is a mixture, as the other two parts have been shown to be. If it is immortal, it should not be dependent for its existence on the condition of the mixture (since that, in any case, is not immortal). Galen is out to argue against the immortality of the soul in this passage, and given the form of the disjunction he presents at the outset, that means that he argues in favour of the rational soul being a mixture.⁹⁴ And in fact he returns to this disjunction further on in the text (787 K), where he presents it again, saying that if the soul is the form of a homoeomerous body – this formulation should not surprise us anymore by now – the thesis that the capacities of the soul follow the mixture of the body is proven beyond doubt. Again, the only other option is that of a Platonic immortal soul:

εἰ μὲν γὰρ εἶδός ἐστιν ὁμοιομεροῦς σώματος ἡ ψυχή, τὴν ἀπόδειξιν ἐξ αὐτῆς τῆς οὐσίας ἕξομεν ἐπιστημονικωτάτην· εἰ δ΄ ὑποθοίμεθα ταύτην ἀθάνατον εἶναι φύσιν ἰδίαν ἔχουσαν, ὡς ὁ Πλάτων ἔλεγεν, ἀλλὰ τὸ γε δεσπόζεσθαι καὶ δουλεύειν τῷ σώματι καὶ κατ΄ αὐτὸν ἐκεῖνον ὁμολογεῖται …⁹⁵

For if, on the one hand, the soul is the form of a homoeomerous body, we shall have the demonstration based on its very substance, which is the most scientific demonstration possible. If, on the other hand, we would take it to be something immortal, having a nature of itself, as Plato said, even then he himself agrees that it is dominated by, and enslaved to, the body …

‘The demonstration’ here refers to the demonstration of the central thesis of QAM, as the preceding sentences make clear. The most scientific demonstration of this thesis is that proceeding from the very substance of the soul, namely the demonstration that shows that the substance of the soul must be the form of a homoeomerous body, i.e. the mixture of elemental qualities that constitutes this body. Again, such a demonstration would logically imply that the capacities of the soul are dependent on the mixtures, since capacities are dependent on the substance of which they are said to be capacities. Again, this is the exact way Galen views the relation between the general thesis that the capacities of the soul follow the mixtures of the body and the stronger thesis that the substance of the soul is a mixture of elemental qualities: if the latter is true, that is the most scientific demonstration of the former, departing from the very substance of the subject under investigation. And it seems as if Galen takes that demonstration to have been given at this point in the text, after the other leg of the dilemma, the option of the Platonic immortal soul, has been rendered implausible by several objections. But, states Galen, even if we would take the soul to be something immortal (which would mean that the central thesis of QAM would not be directly proven from the substance of the soul itself, as it seems it has been now), then we could still prove the central thesis, even by means of what Plato himself has said (also supported by Aristotle and Hippocrates, as Galen goes on to show). Thus, in this part of QAM, following the passage just quoted, he proceeds to take up the other side of the disjunction, although it seems to have already been repudiated. He argues that even if it would be accepted, QAM’s central thesis that the capacities of the soul follow the mixtures of the body remains true.⁹⁶ Therefore, in the part after IV 787 K, Galen does not argue for the substance of the soul being a mixture of elemental qualities anymore. From here on, he only argues for the thesis that the capacities of the soul follow the mixtures of the body, showing that this should be admitted even by those who do not agree with his previous argument that the substance of the soul is a mixture of elemental qualities.

However, in the Platonic section, Galen is concerned with disproving the possibility of the soul existing independent of a specific bodily mixture:

… τολμῶ λέγειν αὐτός, ὡς οὐ πᾶν εἶδος σώματος ἐπιτήδειόν ἐστιν ὑποδέξασθαι τὴν λογιστικὴν ψυχήν. ἀκόλουθον γὰρ ὁρῶ τοῦτο τῷ περὶ ψυχῆς δόγματι τοῦ Πλάτωνος, ἀπόδειξιν δ΄ οὐδεμίαν ἔχω λέγειν αὐτοῦ διὰ τὸ μὴ γιγνώσκειν με τὴν οὐσίαν τῆς ψυχῆς ὁποία τις ἐστιν, ἐκ τοῦ γένους τῶν ἀσωμάτων ὑποθεμένων ἡμῶν ὑπάρχειν αὐτήν.⁹⁷

… I dare to state myself that not every kind of body is suitable to receive the rational soul. For I see this as consequent upon Plato’s doctrine of the soul, but I am not able to state any demonstration for it, because I would not know what kind of thing the substance of the soul is, as long as we assume that it belongs to the class of non-bodily things.

tr. Singer, modified

Interestingly, the ‘daring’ (forms of τολμάω) is a recurrent motif, as we shall see, when it comes to making statements on the substance of the soul that do away with non-bodily options.⁹⁸ For Galen, as we have seen, the soul comes to be when the elemental qualities mix in a certain way in the prime matter. That is to say, without that specific mixture of the qualities, the soul would not come to be. Therefore, he says, not every kind of body is capable of receiving⁹⁹ the rational soul – and it is easy to see how this argument could just as well be extended to the other soul parts that are not under discussion here. But, according to Platonists (or Galen’s reading of them), the soul exists independently of the particular form of the body it inhabits, and therefore does not require any specific mixture of the elemental qualities. A consequence of this view would be, according to Galen, that the soul could inhabit any kind of body, since the conditions of its existence do not include the constitutive properties of a particular kind of body.

In Foet. Form., on the contrary, Galen describes how the higher part of the soul comes to be within an existent hylomorphic construct, depending on the food-distribution of the liver and the heat of the heart. The brain of the infant is constructed later than the two other main organs, and its powers – such as perception, voluntary movement and thinking – come to be only after the completion of the organ. Thus, Galen argues that the activity of the rational soul is dependent on a specific organ that in turn presumes other functions which have previously developed in the human body.

Galen then remarks that ‘this may also be learned from the book in which I show that the soul’s faculties follow the mixture of the body’.¹⁰⁰

To Galen, a soul that exists by itself without being an aspect somehow of a specific bodily construct, is unfathomable. If the soul is considered to be non-bodily, he declares himself unable to understand what it is, as we have seen.

This is not a mere declaration of agnosticism – as it has been read – but much rather a reductio ad absurdum of one side of the previously presented disjunction, namely the Platonic view that the rational part of the soul is immortal and capable of an existence separate and independent of the body.¹⁰¹ Obviously, when Galen states that he is not able to fathom this possibility, even after inquiring into it carefully and considering it often, he does not mean to say that this is merely because of some lack of ability on his part, so that perhaps another, better qualified person could in the meantime have an adequately scientific notion of an immortal soul existing independently of the body. We know enough about Galen’s own estimation of himself and his contemporaries to conclude this much. Again, given the dilemmatic form of the argument, it is an argument for the mortality of the rational part of the soul and, since this was assumed as a consequence of its mortality, for the rational part of the soul being a mixture of elemental qualities.¹⁰² In fact, this becomes clearer in the sentences immediately following, where Galen suggests how much more plausible it is to understand the mixture to be the substance of the soul, since it can account for all the observable qualitative differences that he took to be the starting point of his argument at the beginning of the text:

ἐν μὲν γὰρ σώμασί γε τὰς κράσεις ὁρῶ πάμπολύ τε διαφερούσας ἀλλήλων καὶ παμπόλλας οὔσας· ἀσωμάτου δ΄ οὐσίας αὐτῆς καθ΄ ἑαυτὴν εἶναι δυναμένης, οὐκ οὔσης δὲ ποιότητος ἢ εἴδους σώματος οὐδεμίαν ἐπινοῶ διαφορὰν καίτοι πολλάκις ἐπισκεψάμενός τε καὶ ζητήσας ἐπιμελῶς, ἀλλ΄ οὐδὲ πως οὐδὲν οὖσα τοῦ σώματος εἰς ὅλον αὐτὸ δύναιτ΄ ἂν ἐκτείνεσθαι.¹⁰³

For in the bodies, I see that the mixtures are completely different from each other and very many in number, but with a non-bodily substance able to exist by itself, not being a quality or form of the body, I do not discern any difference, even though I have often considered it and inquired into it carefully – nor, indeed, do I discern how, not being any part of the body, it would be able to extend through the whole of it.

tr. Singer, modified

Again, Galen states that if the soul is to be taken as something other than a form or quality of the body, such as he showed the mixture to be, he does not see a way to explain the observable diversity of individual souls and psychic functions. This clearly refers back to the starting point of the observable differences in the affections and actions of small children. The other option, the soul being the mixture of qualities, simply has superior explanatory value, which is one of the reasons why Galen is more sympathetically disposed towards it, besides it being better matched to his empirical findings. We can find this idea elsewhere in Galen, too, as in the following passage in which he expresses his own carefulness in accepting this (after all) speculative conclusion, as well as the fact that it does seem to be in agreement with his empirical findings:

οὐδὲ γὰρ οὐδὲ τοῦτο τὸ δόγμα, πρὶν ἐν ἅπασι τοῖς κατὰ μέρος ὁμολογουμένοις ἐξευρεῖν, ἐτολμήσαμεν ἀποφήνασθαι. νῦν δ΄ ἐπειδὴ πεπείσμεθά τε τὴν οὐσίαν τῶν δυνάμεων οὐδὲν ἄλλο παρὰ τὴν ποιὰν εἶναι κρᾶσιν, ἅπαντά τε τὰ κατὰ τὰς διαγνώσεις τε καὶ προρρήσεις καὶ θεραπείας ἐπὶ τούτῳ τῷ δόγματι συμφωνοῦνθ΄ εὑρίσκομεν, εὐλόγως, οἶμαι, καὶ τοὺς ἑπομένους ταῖς ἀνωμάλοις δυσκρασίαις τῆς καδίας σφυγμοὺς ἐνταῦθα διήλθομεν.¹⁰⁴

This is because I did not dare to assert this doctrine before finding out if all particular [observations] are in agreement with it. But now, since we have already been convinced that the substance of capacities is nothing but a particular mixture, and, since we have found that all [observations] regarding diagnosis, prognosis and therapy are in agreement with this view, it was reasonable, I suppose, that we would also give an account on this occasion of pulses that follow the anomalous imbalances of mixture in the heart.

tr. Havrda 2017, slightly modified

Again, Galen writes about ‘daring’ to make the statement that the substance of capacities is a mixture, and relates it to the extent of agreement with his practice as a doctor: unlike the Platonic option of the soul as a separate substance, it is a speculative position that is in agreement with his empirical findings. As we have briefly mentioned before, Galen announces in the (earlier) On the Causes of Symptoms that he might have the audacity to make a statement with regard to the substance of the soul in another work (‘αὐτῆς μὲν γὰρ τῆς ψυχῆς τὴν οὐσίαν ἴσως μὲν καὶ κατ΄ ἄλλην τινὰ πραγματείαν ἀποφήνασθαι τολμηρόν’).¹⁰⁵ He then adds the remark that the substance of the soul must be one of two things: either it is something that ‘uses’ the primary organs through pneuma or blood, or it is ‘in’ the primary organs themselves. The last option seems to be completely compatible with my proposed reading of QAM.

It appears as if Galen, after the Platonic section with its arguments against the immortality and supposed separate existence of the soul, indeed considers it proven that the entire soul is a mixture of the elementary qualities. The crucial passage in this respect is Galen’s discussion of the view of Andronicus the Peripatetic (782–83 K), right after the Platonic section. This is not a coincidental position in the text, as should be obvious by now, for Andronicus is credited with espousing the view that the entire soul is a mixture.¹⁰⁶ Andronicus’ position is a reflection of the position Galen’s text is reaching at this point. We have already seen that Galen repeats the conclusion of the Aristotelian section – the lower two parts of the soul (or any parts that are mortal) are nothing else than a mixture of the qualities – right after the discussion of the rational part.¹⁰⁷ At this point, however, Galen takes the discussion a step further and brings in Andronicus, who apparently stated that the substance of the entire soul is either a mixture or a capacity dependent on the mixture:

Ἀνδρόνικον δὲ τὸν Περιπατητικόν, ὅτι μὲν ὅλως ἐτόλμησεν ἀποφήνασθαι τὴν οὐσίαν τῆς ψυχῆς ὡς ἐλεύθερος ἀνὴρ ἄνευ τοῦ περιπλέκειν ἀσαφῶς, ἐπαινῶ τε πάνυ καὶ ἀποδέχομαι τὴν προαίρεσιν τἀνδρός …¹⁰⁸

… and as for Andronicus the Peripatetic, because he dared to speak out on the substance of the soul as a whole, as a free man without unclear complications, I praise him highly and I accept the position of the man …

tr. Singer, modified

Again, we find a form of the verb τολμάω: Galen suggests that it takes some daring to express the view that the substance of the soul is a mixture. What is more, he applauds Andronicus not only for his bravery, but also for his position itself, and accepts it (‘I accept’ is even a rather weak translation of ἀποδέχομαι here, one could also think of ‘I agree with’, or ‘I follow’).¹⁰⁹ He agrees with Andronicus in as far as he states that the substance of the soul is a mixture, and merely disagrees with him in as far as Andronicus adds the possibility that it could rather be a capacity dependent on the mixture.¹¹⁰ Galen’s problem here is with the confused equation of substance and capacity.¹¹¹ That is why he immediately explains (with γὰρ indicating that this is the reason for his disagreement with Andronicus) that the soul has many capacities and is itself a substance (and more specifically, as he adds, a certain mixture of the elemental qualities):

ὅτι δ’ ἤτοι κρᾶσιν εἶναί φησιν ἢ δύναμιν ἑπομένην τῇ κράσει, μέμφομαι τῇ προσθέσει τῆς δυνάμεως. εἰ γὰρ ἡ ψυχὴ πολλὰς ἔχει δυνάμεις οὐσία τις οὖσα καὶ τοῦτ’ ὀρθῶς ᾿Αριστοτέλει λέλεκται … ὑπάρχειν οὐκ ἐγχωρεῖ ἄλλο τι παρὰ τὴν κρᾶσιν, ὡς ὀλίγον ἔμπροσθεν ἐδείκνυτο.¹¹²

… but surely when he says that it [the substance of the soul] is a mixture or a capacity dependent on the mixture, I disapprove of the addition of capacity. For if the soul has many capacities, while itself being some kind of substance, and this has been said correctly by Aristotle … it is not possible for it to be anything else but the mixture, as has been demonstrated a little before.

tr. Singer, modified

Galen does not just recite Aristotelian doctrine here: Aristotle has ‘correctly’ (ὀρθῶς) stated the difference between capacity and substance with regard to the soul.¹¹³ He is accepting the doctrine of Andronicus (as he presents it) that the substance of the soul is a mixture and simply adds: ‘as has been demonstrated a little before’, clearly referring to the Aristotelian section on the substance of the soul being a certain mixture of the four qualities. Presumably, he here also refers back to the arguments against the Platonic position of the immortality and separate existence of the rational part of the soul, since Andronicus’ position concerns the whole soul. After the discussion of all three parts of the soul, the lower two in an Aristotelian and the higher rational part in a Platonic context, we find Galen applauding the view that the entire soul is a mixture of the elementary qualities. He only corrects Andronicus in as far as he neglects the difference between substance and capacity, stating that he disapproves merely of the addition that the substance of the soul may also be a capacity dependent on the mixture (perhaps also because this would be problematic for the soul’s status as a primary cause of movement). The soul’s capacities are dependent on the mixture, but the soul itself has to be a substance, not a capacity. Therefore, it has to be the mixture itself, as has been shown earlier. I see no other way here than to conclude that Galen, at least in this work, adheres to the thesis that the substance of the whole soul is a mixture of elemental qualities. That is to say, that the substance of each of the three parts is a specific mixture constituting homoeomerous parts that primarily exercise the activities of the soul from the respective organs.

2.2 The Mixture of the Rational Soul

However, we have also noticed that Galen reserves a special position for the rational part of the soul. This is evident from the very structure of the text. In fact, with his arguments against the immortality and separate existence of the soul, Galen opens up a very Platonic-looking vertical perspective in which knowledge and the intelligence of the rational part of the soul are connected to the stars by virtue of their related dryness.¹¹⁴ Galen argues against the separate existence of the soul by showing that even its rational part is affected by the elementary qualities of dryness and wetness. Yet, at the same time and through the same argument, he connects the part of the soul that does the understanding to the heavenly realm of the stars. Thus, something of the Platonic ideal of ὁμοίωσις θεῷ remains in place despite the arguments against the immortal soul. In Galen’s cosmos, though, where the traditional Platonic dualism is not affirmed, this ideal may perhaps rather be called a ὁμοίωσις οὐρανῷ or ἄστρῳ (which does not make it less of a ὁμοίωσις θεῷ, however). He reminds us that Plato stated that the soul, by being bound to the body, forgets what it used to know. Galen offers us a rather specific interpretation of this Platonic doctrine:

λέγει γὰρ ὧδέ πως αὐτοῖς ῥήμασιν ἐν Τιμαίῳ κατ’ ἐκεῖνο τὸ χωρίον τοῦ συγγράμματος, ἔνθα φησὶ τοὺς θεοὺς δημιουργῆσαι τὸν ἄνθρωπον ἐνδοῦντας τὴν ἀθάνατον ψυχὴν ‘εἰς ἐπίρρυτον σῶμα καὶ ἀπόρρυτον’ εὔδηλον ὅτι τὴν ὑγρότητα τῆς τῶν βρεφῶν οὐσίας αἰνιττόμενος.¹¹⁵

For he [Plato] says something like this in these very words in the Timaeus, in that part of the work in which he states that the gods craft the human being by placing the immortal soul ‘in a body subject to influx and outflow’. It is quite evident that this is an oblique reference to the wetness of the substance of infants.

tr. Singer, modified

The reference to the substance of infants reminds us of the starting-point of Galen’s text, where he presented the observable differences between children as proof for our given difference in nature. The crafting of the gods concerns the original formation of the human being that would result, according to Galen, in a given nature in accordance with a certain mixture and also, as we now learn, in a (still) disabled state of the faculty of understanding due to predominant wetness.¹¹⁶

But Galen goes on to cite another passage from the Timaeus (44a8–9), which explains that our soul indeed ‘becomes mindless at first’ but is able to ‘acquire a calm’ and ‘become intelligent’ when ‘the stream of growth and nourishment’ that comes upon it is reduced. As Galen explains, the reduction of this stream is to be understood as the change from the wet state of the substance of the infant to a more dried state of the mixture. Note the self-evident manner in which Galen can use the words ‘τῆς τῶν βρεφῶν οὐσίας’ (IV 780 K), the substance of the infants, here to refer to the child’s mixture of elemental qualities, being relatively wet or dry. Note also how obvious it is now in his text that the state of this mixture determines the capacities of the child, i.e. the rational capacity of understanding in this case. The Platonic ‘recollection’ (ἀνάμνησις) of the knowledge that the separate soul obtained in a former heavenly state is given a material (or rather, elemental) twist by Galen, for it is this increasing dryness that brings the soul into a state of understanding (and potentially even likens it to the stars).¹¹⁷

The role of the stars in QAM and the likening of the dryness of the intelligent soul to the dryness of the stars are not random and fit with the Platonic doctrine Galen cites from the Timaeus. There, the divine maker of the universe creates from the mixture of the soul of the universe the immortal parts of the human souls, a number equal to the stars, and assigns to each soul a star. If such a soul, after being incarnated, would succeed in mastering its emotions and living just, it would ‘return again to the dwelling of its kindred star’.¹¹⁸ Particularly in the context of the Timaeus, presented as a follow-up on the Republic, both this mastering and the notion of living justly are about the relation between the several parts of the soul and the extent to which the rational part is in control. In line with this, Galen states that the soul becomes more like a star, if it becomes more understanding and less occupied with the needs and desires of its lower parts. That is to say, in the end, when it lives what is considered a more philosophical life – remember the virtue that the Pythagoreans and Platonists achieved according to Galen, by taking good care of their mixture.¹¹⁹ Thus, when the causal forces that the different soul-parts exercise, are checked and controlled by the rational part in the end, the substance of the soul will become more like the substance of stars. This seems to me an adaptation of the general Platonic doctrine that we also find for example in the (probably near-contemporary) Handbook of Platonism presumably written by Alcinous.¹²⁰ It is stated there that ‘souls which achieved dominance over these affections [sensations, pleasure and pain, fear and anger] and were in no way constrained by them would live justly and return to their kindred star’.¹²¹ Galen merely takes out the notion of the afterlife, which is in fact not needed if we assume that we can liken the substance of our rational soul to that of the stars to some extent during our life.

In QAM, Galen cites one of Heraclitus’ fragments: ‘αὐγὴ ξηρὴ ψυχὴ σοφωτάτη’ (leaving out the addition καὶ ἀρίστη), which is best translated, considering Heraclitus’ other remarks on the ‘moist soul’: ‘a ray of light is the dry soul, wisest’.¹²² Throughout the fragments of Heraclitus there is a basic opposition between the moist and dry soul to be found. The dry soul is associated with wisdom and the light of the heavenly bodies, the moist soul with drunkenness, those desires and acts that man has in common with animals, and even the death of the soul.¹²³ In the same passage of QAM where he cites Heraclitus, Galen calls the stars ‘of the nature of light’ (αὐγοειδεῖς) and ‘dry’ (ξηροὺς).¹²⁴ In PHP, he predicates the same term αὐγοειδὲς of the πνεῦμα that comes from the brain – note that this pneuma has to be moving downwards to permeate and govern the rest of the body, like the intelligence of the heavenly bodies permeates the earthly bodies (see below) – and πνεῦμα is considered (and rejected) in PHP as one of the possible options for the substance of the soul.¹²⁵ This ‘psychic’ πνεῦμα fulfils an important role in the transmission of psychic functions throughout the body (especially that of vision, sensation in general and voluntary motion) because it moves from the brain through the nerves that connect the whole body (likewise the ‘vital’ πνεῦμα that stems from the heart moves through the arteries).¹²⁶

We have seen how one of Galen’s objections against the Platonic doctrine of the soul was that such a soul is not able to stretch out or extend (ἐκτείνω) through the entire body because it is not anything bodily itself.¹²⁷ But, accepting the thesis that the soul is a certain mixture of elemental qualities located in the three main organs, the extension of the soul’s capacities through the rest of the body might still be considered a serious problem (even though the rest of the body is also formed of combinations of the same elemental qualities, the different parts are formed from different combinations and form separate organs).¹²⁸ The πνεῦμα seems to play an important role here. Before we go on, it might be helpful to note that Galen’s notion of (psychic and vital) πνεῦμα as presented in PHP and other works and the thesis proposed in QAM that the substance of the soul is a mixture of elemental qualities need not be at odds with each other in any way. First, in QAM, right after he has approved of the position of Andronicus that the whole soul is a mixture of elemental qualities, Galen states that the Stoics adhere to a similar kind of notion of the substance of the soul, since they believe it to be a kind of πνεῦμα that is composed of a specific combination of the elemental qualities.¹²⁹ Thus, Galen seems to have no problem here in conflating the mixture and the πνεῦμα to get the Stoics on board. But second, and more importantly, Galen explicitly rejects the πνεῦμα as an option for being the substance of the soul already in PHP. First he suggests that, on the basis of his previous findings, one might consider the πνεῦμα in the ventricles of the brain to be either the ‘first home’ of the soul (τὸ πρῶτον οἰκητήριον) if the soul is regarded as incorporeal, or otherwise to be the soul itself, if the soul is regarded as corporeal. But Galen then rejects both of these options:

ἀλλ΄ ὅταν γε συναχθειςῶν τῶν κοιλιῶν ὀλίγον ὕστερον αὖθις αἰσθάνηται καὶ κινῆται τὸ ζῷον, οὐκέτ΄ ⟨οὐδέτερον⟩ οἷόν τε φάναι τῶν εἰρημένων ὑπάρχειν τουτὶ τὸ πνεῦμα. βέλτιον οὖν ὑπολαβεῖν ἐν αὐτῷ μὲν τῷ σώματι τοῦ ἐγκεφάλου τὴν ψυχὴν οἰκεῖν, ἥτις ποτ΄ ἂν ᾖ κατὰ τὴν οὐσίαν – οὔπω γὰρ περὶ τούτου σκέψις ἥκει – τὸ πρῶτον δ΄ αὐτῆς ὄργανον εἴς τε τὰς αἰσθήσεις ἀπάσας τοῦ ζῷου καὶ προσέτι τὰς καθ΄ ὁρμὴν κινήσεις τοῦτ΄ εἶναι τὸ πνεῦμα, διὸ καὶ κενωθέν, ἄχρις ἂν αὖθις ἀθροισθῇ, τὴν μὲν ζωὴν οὐκ ἀφαιρεῖσθαι τὸ ζῷον, ἀναίσθητον δὲ καὶ ἀκίνητον ἐργάζεσθαι. καίτοι γε, εἲπερ ἦν αὐτὸ ἡ τῆς ψυχῆς οὐσία, συνδιεφθείρετ΄ ἂν αὐτῷ κενουμένῳ παραχρῆμα τὸ ζῷον.¹³⁰

But when presently, after the ventricles have been closed up, the animal regains sensation and motion, it is no longer possible to accept either alternative. It is better, then, to assume that the soul dwells in the actual body of the brain, whatever its substance may be – for the inquiry has not yet reached this question – and that the soul’s first instrument for all the sensations of the animal and for its voluntary motions as well is this pneuma; and therefore, when the pneuma has escaped, and until it is collected again, it does not deprive the animal of its life but renders it incapable of sensation and motion. Yet if the pneuma were itself the substance of the soul, the animal would immediately die along with the escape of the pneuma.

tr. De Lacy

So the πνεῦμα is neither the ‘first home’ of the soul, nor the soul itself. What the soul itself is, remains unanswered here, although it is said to dwell in the body of the brain – which is perfectly compatible with our analysis of QAM.¹³¹ The πνεῦμα is rather defined as the soul’s first instrument for the sensations and voluntary motions.¹³² Since the function of the πνεῦμα is one of transmission, it is unsuitable to be identified with the soul itself or the substance of the soul, which is located in the three main organs, whereas it can be considered an instrument of the soul.¹³³ It is the stuff through which the soul stretches itself out through the body, and which has its ἀρχή in the main organs. Sensations and voluntary motions, after all, require a connection to all ends of the body. Thus, Galen’s notion of the soul as πνεῦμα and of the substance of the soul as a mixture, are not only compatible but can even support each other. Questions remain on the precise relation of πνεῦμα and the mixture, particularly as regards to the stuff of the πνεῦμα: presumably, it must be very fine, as it travels quickly throughout the body, but it must also have some resemblance to the mixtures that the organs are constituted of in order to fulfil its communicative and transmissive function. But these questions cannot be further pursued here.

We have seen how the psychic πνεῦμα is said by Galen to have some resemblance to light, and how it moves from the brain, through the nerves, to the rest of the body.¹³⁴ Galen only uses the term αὐγοειδῆ for the πνεῦμα that comes from the brain (and that forms the basis for the capacity of vision), and not for the ‘vital’ sort of πνεῦμα that comes from the heart, which is in line with the exclusive connection of the rational part of the soul to the heavenly bodies. In the epode of UP, Galen dwells on the amazing intelligence of the heavenly bodies, which permeates everything below:

τίς δ΄ οὐκ ἂν εὐθὺς ἐνεθυμήθη νοῦν τινα δύναμιν ἔχοντα θαυμαστὴν ἐπιβάντα τῆς γῆς ἐκτετετάσθαι κατὰ πάντα τὰ μόρια; (…) ἀλλ΄ ὅμως ἐνταῦθα φαίνεται νοῦς τις ἀφικνούμενος ἐκ τῶν ἄνω σωμάτων, ἅ καὶ θεασαμένῳ τινὶ παραχρῆμα θαυμάζειν ἐπέρχεται τὸ κάλλος τῆς οὐσίας, ἡλίου πρῶτον καὶ μάλιστα, μετ΄ αὐτὸν δὲ σελήνης, εἶτα τῶν ἀστέρων, ἐν οἷς εἰκὸς, ὅσῳ πέρ ἐστι καὶ ἡ τοῦ σώματος οὐσία καθαρωτέρα, τοσούτῳ καὶ τὸν νοῦν ἐνοικεῖν πολὺ τοῦ κατὰ τὰ γήινα σώματα βελτίω τε καὶ ἀκριβέστερον.¹³⁵

Who would not immediately infer that some intelligence possessing amazing power treads the earth and extends through its every part? (…) But even here some intelligence appears to be reaching us from the bodies above, and the beauty of their substance forces anyone that sees them to be amazed at once, that of the sun first and foremost, that of the moon after that, and next that of the stars, and it is reasonable to suppose that the intelligence that dwells in them is exactly that much better and sharper than that [which dwells] in the earthly bodies as the substance of their body is purer.

tr. May, slightly modified

The marvellous usefulness of the parts that is praised throughout UP is grounded in an intelligence that primarily dwells in the heavens. In his Epode Galen both affirms the dependence of the observable teleological order on an intelligent principle, as well as the affinity of that principle with our rationality. Some kind of intelligent force reaches down from the heavenly bodies, apparently its primary location, and extends through every part of the earthly beings – as we observed, forming a beautiful analogy with the extension of the psychic pneuma from the brain downwards to the rest of the body.¹³⁶

In this analogy between our brain and the heavenly bodies, the notion of a κοινὴ οὐσία is operative, too, for the difference between our intelligence and that of the heavenly bodies is not essential but gradual. It is grounded in the difference in substance of their respective bodies: how intelligent must the heavenly bodies with their pure substances be, asks Galen, when we consider that the intelligence of men like Plato, Aristotle, Hipparchus and Archimedes came to be in something that moist or muddy (ἐν βορβόρῳ τοσούτῳ)?¹³⁷ Again, there is a direct correspondence between the purity of the bodily substance, or its relative dryness, and the quality of the intelligence of a given being. There is a vertical hierarchy in the cosmos, in which the higher realms have a greater degree of dryness and purity, and therefore of intelligence. Their superiority emanates and is communicated to the lower realm: the light and intelligence of the heavenly bodies reaches down, infusing the air and bodies below them. The human being, looking up and seeing the heavenly bodies, is brought into that state which Plato in his Theaetetus designated as the only possible beginning of philosophy – amazement (θαυμάζειν in the last quotation from UP).¹³⁸

What we can gather from these quotations is that the state of a given substance, and thus the activities it can undertake, is strongly determined by the overall cosmic organization of qualities, in which some qualities predominate certain regions. Thus, because dryness predominates in the higher regions and wetness in the lower ones, a mixture with predominant dryness might be more apt to generate the activities of the higher regions. It seems as if Galen, in line with tradition, generally associates the qualities of hotness and dryness more with activity and the qualities of coldness and wetness with passivity:

Just as cold produces laziness, immobility and weakness, so heat produces energy, movement, and the strength to act. That is why the beginning of youth and wine arouse movement and power, while old age and chilling drugs produce laziness and weakness; they lead, in time, to the annihilation of actions and movements.¹³⁹

But this notion, that a specific mixture generates specific states and activities and that we can have knowledge of what kind of mixture causes what kind of state and activity, is where the possibility of a second formation of our mixture enters, after that of the first by nature: as soon as our rational faculty is functioning, we can and should develop our soul by adopting a way of life that further enhances our mixture in such a way that we can become more virtuous and understanding.¹⁴⁰ That is to say, after being given a certain mixture in the first place, by the gods or nature, we can continue this divine formation ourselves, because we have a rational soul. As Galen remarked at the very beginning of QAM:

… διὰ τῶν ἐδεσμάτων τε καὶ πομάτων ἔτι τε τῶν ὁσημέραι πραττομένων εὐκρασίαν ἐργαζόμεθα κἀκ ταύτης εἰς ἀρετὴν τῇ ψυχῇ συντελέσομεν, ὡς οἱ περὶ Πυθαγόραν τε καὶ Πλάτωνα καὶ τινες ἄλλοι τῶν παλαιῶν ἱστοροῦνται πράξαντες.¹⁴¹

… for through what we eat and drink and more generally through our daily practices, we bring about good mixture, and through this [good mixture] we shall achieve for the soul a state of virtue, as those around Pythagoras and Plato and some others among the ancients are reported to have done.

This formative capacity of the rational part of the soul is crucial for Galen. It is not just what makes the difference between man and the other animals and guarantees the possibility of ethics. It also contains man’s potential to reach his τέλος. The state of virtue that Galen refers to here is not an accidental attribute. Like most of the ancient thinkers, Galen’s notion of man is that of an essentially unfinished being that has to play its own creative part before it can be said to have reached completion, thus continuing the role of its divine maker to which it always has some form of analogy. We will return to this theme below (paragraph 4).

For now, what is important to observe for our purposes here, is that Galen retains the vertical connection, the kinship between the heavens and the rational part of the soul offered in Plato’s Timaeus, although he gives it a more material basis, namely that of relative dryness. This aligns with his notion of the substance of the soul being a mixture of the four elemental qualities as well as with his association of the rational soul with the stars. Even though he argues against Platonists where it regards the separate existence and immortality of the soul, Galen retains the special connection of the rational part with the heavens that is fundamental for Platonic ethics. This must be the main reason why he treated the rational part of the soul in a discussion separate from the other two parts in a Platonic context.

2.3 Conclusion

To conclude this section, I believe that on the basis of our discussion of the textual evidence, we have established the following things. Galen, in what I have called the Aristotelian section (773–5 K), argues that the substances of the non-rational parts of the soul are certain mixtures of the elementary qualities forming homeoemerous bodies, that is to say, they are the formal aspect in a hylomorphic composition with prime matter. He argues for the same conclusion for the rational part of the soul in what I have called the Platonic section (775–82 K). After both of these sections he applauds and accepts the view that the substance of the entire soul is a mixture (782–3 K). Furthermore, he takes the proof that the substance of the soul is a mixture as the most scientific proof for his central thesis that the capacities of the soul follow the mixture of the body. However, the rational part of the soul has been assigned a somewhat exceptional position that retains something of a Platonic perspective, in line with Galen’s classing of QAM as a work ‘On Platonic philosophy’. As we shall see below (paragraph 4), this kinship with the heavens of the rational part of the soul plays an important role in the possibility of ethical philosophy in the context of a work that emphasizes the determination of the soul’s activities and affections by the bodily mixture and even identifies the substance of the soul with that mixture. But first, since the reading of QAM presented above differs from much of the preceding scholarly tradition and is not without problems, we shall discuss some of the possible objections to my view that Galen argues for the thesis that the substance of the soul is a mixture.

3.1 Preliminary Remarks

Several scholars have argued that the thesis of the substance of the soul being a certain mixture should somehow not be ascribed to Galen or not be viewed as an expression of his own doctrine. We shall critically discuss their views in this section. A few preliminary remarks are in order, however. It is certainly true that QAM is both a somewhat ambiguous work in itself and stands out in the Galenic corpus for its more speculative position. It is also true that Galen seems to firmly reject any knowledge of the substance of the soul in some of his other (partly later) work. On the other hand, as we have seen, Galen also refers to ‘what has been shown’ in QAM in other later works (such as HNH, Loc. Aff. and Foet. Form.), which are considered as works that reflect genuine Galenic doctrine. Thus, apparently Galen himself does take QAM to be consistent enough with these other works to refer to its arguments as support for them. Moreover, as we have also seen, the doctrine that the substance of the soul is a mixture is in line with, and based on, much of his earlier work that is presupposed in QAM. Also, QAM seems to be the only place in the Galenic corpus where Galen actually discusses the question of the substance of the soul at some length. Therefore, it might be a dubious strategy to dismiss what he states there merely on the basis of his reluctance to actually discuss the subject in other works. Finally, given that Galen classified the work as one concerning ‘Platonic philosophy’, it may make sense for him to enter somewhat more speculative or philosophical terrain in this treatise than in one, say, treating of the pulse or respiration. For these reasons, I think that characterizing QAM as vague, of lower quality than other Galenic work, or mere propaganda for the office of doctor, and using such evaluations to set the work aside and skip over its integration into the rest of the Galenic corpus, as has been done in some recent scholarship, will not do.

The difficulty with Galen’s speculative boldness in QAM goes back a long way in scholarship: a certain unease with QAM’s stronger thesis seems already manifest in the editing work of Müller, who omits some of the evidence by bracketing the two sentences after the Aristotelian section that most clearly affirm it.¹⁴²

Moraux seems to be an early exception in modern scholarship by taking the stronger thesis as the expression of Galen’s view, albeit with a somewhat careful expression: ‘In seinen letzten Jahren scheint er davon überzeugt, daβ die Zustände des Körpers das Psychische eben deswegen zu beeinflussen vermögen, weil die Seele nichts anderes ist, als eine besondere “Mischung” der elementaren Bestandteile des Körpers’.¹⁴³ Moraux explains the difference with other, earlier works (UP and PHP) as a development towards ‘Naturalismus’. The problem with a developmental view is obvious: as soon as we find another expression of scepticism or agnosticism after QAM, the thesis of a linear development becomes difficult to maintain. Such has happened, of course, with the more recent discovery of Galen’s On my own Opinions (Prop. Plac.).

A comparable but more careful position is found in Tieleman: ‘In PHP Galen still clings to an agnostic position as to the substance of the soul. Nonetheless he already links psychic part and bodily part (PHP 6.2.5 [=V 515.12–516.1 K]). In the work of his late age, QAM, he takes the next step of actually identifying the substance of the soul with the form of the three main bodily organs, taking form in the sense of the blend of elementary qualities distinctive of each organ. In effect he comes out in favour of the Peripatetic view of the substance of the soul as the form of the body, combining this with the Platonic tripartition-cum-location’.¹⁴⁴ Mario Vegetti has argued among similar lines in an insightful chapter on Galen’s interpretation of the Timaeus: ‘Il confronto di Galeno con il Timeo riprende nel Quod Animi Mores (QAM) nel punto, si può dire, dove esso si era interrotto nel PHP. L’anima è divisa in tre parti, che hanno la loro localizzazione somatica in tre organi ‘omeomeri’, rispettivamente il cervello, il cuore e il fegato … L’anima non sta negli organi somatici come un inquilino in un appartamento. Sarà meglio parlare, seguendo un tesi affermatasi nella scuola di Aristotele, forse ad opera di Andronico di Rodi, dell’anima come ‘temperamento’ (krasis) o come facoltà (dynamis) derivante dal temperamento; anzi, Galeno ritiene sia meglio eliminare del tutto il riferimento alle facoltà e intendere l’anima soltanto come temperamento dell’organo, dando così una interpretazione molto restrittiva della definizione aristotelica dell’anima come forma del corpo’.¹⁴⁵

I think the analysis given in the first two paragraphs above supports the position of Moraux, Tieleman and Vegetti. However, rather than suggesting a one-way development as Moraux does, my conclusions are restricted to the content of QAM itself and its congruence with both earlier and later work. These conclusions can be taken as an elaboration of the suggestions made by Tieleman and Vegetti. Without trying to unify Galen’s work into one coherent and consistent doctrine with respect to the substance of the soul, we can simply acknowledge that he chose to enter somewhat more speculative terrain in QAM, consistent with the question he ‘dares’ to ask there. At the same time, we should acknowledge, based on the analyses offered above, that this speculation is in line with the rest of his work, which makes this particular speculative position, as we have noted above, a reasonable one for Galen.¹⁴⁶

On the other hand, Garcia-Ballester, Lloyd, Donini and Singer all seem to agree – though, not all for the same reasons – that Galen does not actually argue for the thesis of the substance of the soul being a mixture in QAM. What these scholars have in common with regard to their interpretation of QAM is the development of an interpretational strategy that enables them to avoid taking the thesis as a serious expression of Galenic doctrine. In other words, their agreement consists in the conviction that there has to be a reason for the presence of this conclusion in QAM other than it being an expression of Galen’s own view. An important and legitimate motive behind the development of such a strategy for all of them seems to be the apparent incongruence of QAM’s stronger thesis with some of Galen’s other work. Before discussing their views in more detail, I would like to briefly go into this general problem, first. The comparison is often made with PHP, which is dated much earlier and therefore not very compelling on its own (one could still argue for a developmental thesis in line with Moraux). But the comparison is also made with Prop. Plac., which is more interesting, because it is later than QAM and seems to advocate the same ‘agnosticism’ as expressed in PHP and other works. Because Prop. Plac. is a late work in which Galen looks back on his own writings, it would be the most problematic case in this regard. If he clearly expresses his agnosticism with regard to the substance of the soul in that work, should we then not conclude that he has always remained agnostic and that, indeed, we should not take the strong thesis of QAM too seriously? In the next paragraph we shall take a small detour to discuss the relation between QAM and Prop. Plac., before returning to the scholarly debate.

3.2 QAM and Prop. Plac.

In Prop. Plac., Galen explicitly claims several times that he does not know what the substance of the soul is.¹⁴⁷ Unfortunately, he does not refer to QAM at all. This is remarkable in itself, for several reasons: (1) he did refer to QAM in many of his other later works, (2) he frequently refers to many of his other works in Prop. Plac. and (3) it is obvious that the subject at hand in Prop. Plac. has strong affinities to QAM at some points. Whatever the reason for the absence of any explicit reference to QAM in Prop. Plac., I do not think it is legitimate to conclude from the apparent contradiction concerning what Galen has to say on the substance of the soul in both works, that what he has to say in QAM is not to be taken seriously. In this regard, it is important to note much rather the strategic aim of Prop. Plac. Galen, finding himself in a similar situation as the poet Parthenios, as he states, is defending himself against wrong interpretations of his works. He explicitly presents this predicament as the very reason for writing the work. In the apt words of Aileen Das: ‘this work seems to be as much an apology as a career conspectus’.¹⁴⁸ More specifically, Galen remarks that people have often misunderstood the status of some of the things he wrote. Thus, there has apparently been a mix-up of things he has claimed to know and things he has merely claimed to find plausible (πιθανός). It seems likely, considering the apologetic and careful tone of the whole text, that others have taken some views that Galen has presented as plausible as if they were presented by him as having the status of scientific knowledge.¹⁴⁹ After these introductory remarks, Galen starts denying all knowledge with regard to ticklish subjects such as the creation and creator of the universe, the gods, the substance of the soul and the celestial bodies. As if he had never speculated on any of these subjects in his work (which he had, not only in QAM, but also in UP or his commentary on and summary of the Timaeus, for example). Thus, Galen is here drawing a strict boundary between what he claims to have knowledge of, and what he could merely present as plausible, or as the most plausible position on a certain subject, on the basis of what he does know.¹⁵⁰ Moreover, we can derive from QAM that Galen met with some kind of indignation over the views he presents there: they were apparently judged to be destructive of the beautiful fruits of philosophy (QAM IV 814 K). One might think here of the well-known Stoic metaphor of philosophy as an orchard or garden, where logic is the protective fence around the orchard, physics the trees or plants and ethics the fruit or produce.¹⁵¹ Galen’s physical doctrines were accused of being unfruitful in the field of ethics, so it seems. And it is not very difficult to see why, since in ancient and modern times alike more ‘physicalist’ doctrines on human nature often meet with some worry in this regard. As we have noted, Galen himself frequently spoke of ‘daring’ to speak out on the substance of the soul, admitting that it is both a speculative and a sensitive subject and possibly also that his own thesis might be considered to have negative implications for the possibility of ethics.

While Galen, in QAM, might have merely wanted to float the speculative position that is most compatible with the knowledge he has of the human being, tradition shows that it is easy to forget about this distinction and to ascribe to this speculative position in a work on Platonic philosophy the same status as the more empirically verified knowledge that it has to match in order to be accepted as the most likely position on a speculative subject.¹⁵² I think it is crucial to recognize this difference in status, which Galen himself emphasizes in Prop. Plac. Surely this is preferable to dismissing his writing on the substance of the soul as simply incongruous with his ‘agnosticism’, or as serving some other function than an expression of his own thought.

Despite the fact that Galen does not explicitly refer to QAM in Prop. Plac., the views he elaborates in QAM certainly surface there. In paragraph 7, we find something quite reminiscent of what we read in QAM. Interestingly, we find it right after Galen again remarks that he does not know what the substance of the soul is:

εἶναί τε τούτων γένε(σιν ἐκ) τῆς ποιᾶς κράσεως τῶν τεσσάρων στοιχείων, καὶ εἴπερ (ἡ ψυχὴ ἅμα τῷ) διαπλάττ(ομενῳ) σώματι, τὴν γένεσιν ἔχει, (διὰ δὴ τ(ὴν) τῶν τεσσάρων στοιχείων κρᾶσιν αὐτὴν γίνεσθαι, οὐκ ἄλλ(ης) (μὲν) οὔσης τῇ (ψυ)χῇ γενέσεως, ἄλλης δὲ τῷ αἰσθητικῷ σώματι· μ(ὴ γὰρ) εἶναί που ψυχῆς οὐσίαν καθ΄ ἑαυτήν, (ἀλλ΄ οἷ)ον εἶδός τι τοῦ σώματος ὑπάρχειν αὐτήν· ἄκουε δέ μου λέγοντος εἶδος ὡς πρὸς τὴν τῆς ὕλης ἀντίθεσιν, ἥν ἄ(ποιον) εἶναι νοοῦμεν ὅσον τὸ ἐφ΄ ἑαυτῇ.¹⁵³

And that the generation of them [the perceptive bodies] is from the specific mixture of the four elements, and if the soul has its generation together with the formation of the body, then it itself comes to be because of the mixture of the four elements, since there is not one generation of the soul, and another of the sense-perceiving body; and I suppose that there is not a substance of the soul existing by itself, but that it is a kind of form of the body; understand when I say form I mean the opposite of matter, which we understand to be without quality taken in itself.

Here, almost immediately after saying that he does not know the substance of the soul, Galen proceeds to suggest that the soul – like the organs of perception – comes to be from the mixture of elements, that the soul does not have a generation separate from that of the body, that there is no separate substance of the soul, and that the substance of the soul is rather a kind of form of the body. Particularly his explaining remark at the end is reminiscent of QAM: the form he is referring to here is the opposite of a matter without quality. We have seen that for Galen the most basic building blocks of anything in the cosmos are this prime matter and the four qualities that mix in it. That implies that, like in QAM, Galen is suggesting here that the mixture of qualities (and not the form of any more complex thing such as an organ, the matter of which can after all not be without quality) is the form of the body, i.e. the soul. How is it possible that Galen can say all this about (the substance of) the soul, while at the same time proclaiming that he does not know what the substance of the soul is? The answer to this question lies in the distinction he sets out at the beginning of Prop. Plac., between what he thinks he knows and what he thinks is plausible. The εἶναι cited at the start of this passage is dependent on a previous εὔλογον νομίζω, ‘I consider it reasonable’, and as we have seen Galen also adds an extra που, ‘I think/suppose’, when he gives his take on the actual substance of the soul. By contrast, at the start of paragraph 7, and again after the passage cited above, where he denies knowledge of the substance of the soul, he expresses himself in a much stronger vocabulary, using forms of ἀγνοεῖν and γιγνώσκω. Thus, Galen, in this late apologetic work, states that although he does not know what the substance of the soul is, he does consider it reasonable that it is a mixture of elemental qualities. This is completely in line with QAM, where he presents us two options with regard to the substance of the rational part of the soul: either it has a separate, incorporeal existence, or it is the form of a homoeomerous body.¹⁵⁴ In QAM he then proceeds to show how the former view is more unlikely than the latter by enumerating problems with it.

Further on in Prop. Plac., we find another passage reminiscent of QAM, particularly of the passage on the relation between substance, activities and capacities:

Περὶ ⟨δὲ⟩ τῆς οὐσίας τῶν ψυχικῶν δυνάμεων, ὅτι ψυχὴ ἔχομεν, ἐπίσταμαι ὥσπερ πάντες ἄνθρωποι, θεώμενοι μὲν ἐναργῶς τὰ διὰ τοῦ σώματος ἐνεργούμενα, βαδιζόντων καὶ τρεχόντων ⟨καὶ⟩ ἔσθ΄ ὅτε καὶ παλαιόντων αἰσθανομένων τε πολυειδῶς· ἐννοοῦντες δὲ τῶν ἔργων τούτων αἰτίας τινὰς ὑπάρχειν ἔκ τινος ἀξιώματος φυσικοῦ πᾶσιν ἡμῖν πιστοῦ, καθ΄ ὅ μηδὲν ἀναιτίως γίνεσθαι νοοῦμεν, ἀλλὰ διὰ τὸ μὴ γινώσκειν, ἥτις ἐστὶν ἡ αἰτία τῶν ἔργων τούτων, ὅνομα θέμενοι ἀπὸ τοῦ δύνασθαι ποιεῖν ἅ ποιεῖ, δύναμιν [εἶναι] τῶν γινομένων ἑκάστου ποιητικήν …¹⁵⁵

With regard to the substance of the psychic capacities, that we have a soul, I know as all men do, because we clearly see the activities performed through the body, walking and running and sometimes also wrestling, and sense-perception of many kinds, and because we understand that there are certain causes of these actions, on the basis of a natural axioma trusted by all of us, according to which we consider nothing to happen without cause; but because we do not know what the cause of these actions is, we postulate a name based on the being able to do the things that it does, a capacity as the efficient cause of each of the things that happen …

As in the passage at the beginning of QAM (IV 769–70 K), the δύναμις is explained as a mere appellation (ὄνομα) because the true efficient cause of the activities, the substance (οὐσία), is unknown. The fact that the activities are there prove that soul exists as their cause (just as the fact of well-designed creatures proves that an intelligent creator exists), but because we do not know what soul itself is, we name the causes of the activities in terms of capacities, while it is really the substance that is the cause, that is able to do what it is observed to do.¹⁵⁶ As in QAM, where it was aloe, Galen gives examples of the capacities of substances used for medical purposes, scammony and medlar in this case. He proceeds to enumerate two basic positions with regard to what the soul is, which we recognize from our previous discussion. First, there are those who state that incorporeal capacities ‘inhabit’ (ἐνοικεῖν) the perceptible substances (ταῖς αἰσθηταῖς οὐσίαις, this term seems to refer to the homoeomerous bodies, at least it does so for Galen). This is a view Galen obviously does not sympathize with. It is the same view that is mentioned in QAM as the very reason to clarify the same matter just cited from Prop. Plac., namely that the actual cause is the substance itself and that the capacity is nothing other than an appellation based on the recognition that some substance can undertake a certain activity and cause a certain effect. According to the second position, the substances themselves act according to their own particular nature (οἱ δὲ αὐτὰς ἐνεργεῖν τὰς οὐσίας κατ΄ ἰδίαν ἑκάστης φύσιν). The latter view is in accordance with the notion that the substances themselves are the true efficient causes of activities, presented just a little earlier and argued for in QAM. This view is again subdivided, according to the particular take on what the substance is: either a mixture of the four elements, or a non-mixed kind of composition of primary bodies (ἢ ποιᾶς συνθέσεως τῶν πρώτων σωμάτων). Within the latter category, there is another fourfold division. Some say that these primary bodies are indivisible (ἄτομα), others call them unlinked (ἄναρμα), others say they are without parts (ἄμερη), and others, still, call them homoeomerous (ὁμοιομερῆ). Within this subdivision into the substance as mixture and as unmixed composition, it is obvious Galen sympathizes with the first option and not with any of the ones given after that. Those seem to represent various atomists (ἄτομα and ἀμερῆ), Asclepiades of Bithynia (ἄναρμα) and possibly Anaxagoras (ὁμοιομερῆ; Galen’s problem with this view is likely to be that the homoeomerous bodies are not unmixed but should rather be further subdivided (conceptually) in matter and mixture of the four qualities).¹⁵⁷ Again, Galen states, some think the soul is an incorporeal substance (presumably the Platonists are meant here) and others think it is pneuma (the Stoics). Galen also clearly rejects both of these latter views, elsewhere. Finally, others hold that the soul does not have some existence of its own (μηδὲ εἶναι τινα ὕπαρξιν αὐτῆς ἰδίαν). This view is obviously favoured by Galen, since – besides being much more compatible with the rest of Galen’s work in general – in the passage we cited above, he had already stated that he thinks the soul does not exist on its own.¹⁵⁸ He proceeds to specify this option as follows:

… καθάπερ ἄλλοι μηδ΄ εἶναί τινα ὕπαρξιν αὐτῆς ἰδίαν, ἀλλὰ τὴν ἰδιότητα τῆς τοῦ σώματος οὐσίας, ὧν ποιεῖν πέφυκε, τούτων ἔχειν λέγεσθαι δυνάμεις, οὐκ οὐσ⟨ι⟩ῶν τινων ἐκείνων ἰδίαν φύσιν ἐχουσῶν, ἀλλὰ τῆς ἐνεργούσης οὐσίας καὶ αὐτῆς πρὸς τὰ γινόμενα δι΄ αὐτῆς τε καὶ ὑπ΄ αὐτῆς δυνάμεις ἔχειν λεγομένης, ὧν πέφυκε δρᾶν.¹⁵⁹

… and according to others [the soul] does not have some existence of its own, but the specific nature of the substance of the body, is said to have capacities of those things which it does naturally; it is not the case that the capacities possess the particular nature of certain substances, but the substance that is acting, that is to say: it with regard to the things that happen through it and because of it, is said to have capacities, for the things which it does naturally.

Again, we find the view that it is the bodily substance, and its peculiar nature, that is the cause of activity which we tend to attribute to a substance we call soul, while this very bodily substance is additionally said to have certain capacities for the things that it does. This seems to be the same view as the one that was contrasted with the notion of incorporeal capacities inhabiting the homoeomerous bodies before, namely that it is rather the substance itself (i.e. the homeomerous body through its constituent qualities) that is the cause of activity, and that it is merely said to have capacities because we observe that it does what it does without perceiving the substance itself as the cause of activity. Previously, Galen gave several options as to what this substance might be, but now, unfortunately, he does not specify what those espousing this view hold to be the substance of the body. Galen proceeds to state that he has positioned himself somewhere midway in this discussion. On some other subjects he has spoken clearly, with regard to some of those he has known the truth and with regard to some others he did not know anything at all. In the discussion at hand, however, he goes as far as stating what is plausible (πιθανοῦ). Although he thinks that it would be better to have a sure knowledge on this subject, as he has on some others on which he spoke out clearly, he also thinks it better not to be convinced that one has sure knowledge as long as a definitive demonstration is lacking. Finally, he characteristically adds that knowledge of these matters is not necessary for medicine and ethics.¹⁶⁰ The ‘middle position’ that Galen says he has been taking, thus refers to the epistemological status of his position in this debate, rather than to a position in between the views of the soul being incorporeal or not having a separate substance. As to those views, it is clear enough, I think, where Galen’s sympathies lie – namely with the view that the soul (i.e. the cause of activity) does not have a separate existence and is rather a bodily mixture – but he simply qualifies this subject as outside the current domain of matters that can be proven definitively and considers his views on the matter to be plausible rather than having the status of certain knowledge.¹⁶¹ That does not mean, however, that he does not find his position more plausible than that of someone who holds that the soul is a separate incorporeal substance inhabiting the body (which would be more at odds with the empirical evidence), or let alone that he does not have a view on the subject altogether. Aristotle ascribes to ethical philosophy a different status, another degree of certainty than he ascribes to the theoretical sciences. Yet that has not stopped us from writing libraries on ‘Aristotle’s ethics’. Is it curious for Galen, with his medical and empirical orientation, to deny to philosophical psychology the same kind of certainty as to the study of the human body and its workings and yet have some more or less definite thoughts about it because some of those thoughts may be more or less in congruence with his knowledge of the body?

3.3 Critical Discussion of Some Previous Scholarship on QAM

In scholarship on Galen it has often been held that Galen does not really hold the view that the soul is a mixture or does not present this view as his own in QAM.

Garcia-Ballester remarks that Galen in PHP and other works explicitly refuses to offer his opinion on the corporeality or incorporeality of the soul, and that in QAM he ‘maintains the same attitude surrounded by a certain vagueness’.¹⁶² It seems that, according to Garcia-Ballester, the differences in content between PHP and QAM are to be understood as due to the latter’s vagueness, as opposed to a development or the context of a different question or point of departure. This is a thought that finds ample resonance in later scholarship.¹⁶³ The vagueness can again be accounted for in various ways, according to Garcia-Ballester. First, he states that ‘The arguments used by Galen in Quod animi mores relating to the subject of the connection between body and soul are not aimed at expounding his personal position. They are hypothetical arguments concerning what Aristotle is committed to’.¹⁶⁴ This fairly general line of interpretation (practically the whole text is about the connection between body and soul, including passages with arguments relying on Plato, the Stoics and Hippocrates) has been worked out in more detail and with much more nuance by Singer, who aims to explain ‘some of the more extreme statements and some of the apparent inconsistencies’ by arguing for the ‘hypothetical nature’ of Galen’s arguments.¹⁶⁵ According to Singer’s reading of QAM, we are to conjecture a ‘conditional clause with the fundamental sense: ‘if Aristotle is right”, where Galen says or implies that the substance of the soul must be a mixture of the body.¹⁶⁶ It is certainly the case that Galen’s use of Aristotelian doctrine is crucial with regard to the thesis that the substance of the soul is a mixture. It is also the case that in QAM Galen uses, quotes from and interacts with various other authors in a way that can make it difficult to disentangle their views from his own. However, I think Singer stretches this strategy too far, perhaps in an attempt to neutralize the boldness of QAM somewhat, and to save Galen from being inconsistent with regard to his ‘agnosticism’. The text-analysis offered above in the first two paragraphs, combined with the noted similarities in other works including Prop. Plac., suffices, I think, to prove that the view that Galen is merely presenting an Aristotelian position in QAM, rather than his own, cannot be maintained. I think it is true, though, that Galen’s own position on the matter is close to an Aristotelian one (though with some differences, as has been noted, particularly the emphasis on the primacy of the smallest units when it comes to the location of soul and the seemingly reductionist notion of capacities) and that, in QAM, he is out to back his own position through the use of the authority of Aristotle, among others.¹⁶⁷ We may rather conclude, I propose, that Galen’s theses in QAM are Aristotelian to the extent that Galen’s views on the soul are Aristotelian.

The second interpretational strategy that Garcia-Ballester suggests to account for QAM’s ‘vagueness’ is ‘the involvement of socio-professional interests in motivating the formulation of such an extremely radical naturalism by Galen’.¹⁶⁸ This again fairly general line of interpretation is worked out in more detail by both Donini and Lloyd. Besides being quite unelegant and methodologically problematic because it involves both speculating on the author’s intentions and suggesting them to be somewhat dubious, there are other problems with this strategy as well. In Garcia-Ballester’s case at least, it is based on a confused understanding of the relation between doctor and philosopher in QAM. Garcia-Ballester writes that Galen ‘asserts that medicine is superior to philosophy for the total understanding of man’.¹⁶⁹ To back this claim, he cites as evidence one passage, in which Galen states that those of the philosophers who think all humans are receptive to virtue and those who hold that no one chooses justice for its own sake both have a partial view of human nature.¹⁷⁰ Garcia-Ballester then makes it seem as if there is a contrast here with the doctor (who is factually absent in the text), who would apparently be able to have a complete view. For one thing, this interpretation ignores Galen’s repeated expressions of appreciation for the ancient philosophers, as he consistently presents them as paradigms of the possibility of ethical progress through the knowledge of his central thesis in QAM. In fact, Galen expresses such admiration shortly after the passage cited by Garcia-Ballester:

εἰ γάρ τις, οὐκ ὢν ἐπιτρίπτων τε καὶ φιλονείκων, ἐθελήσειεν ἐλευθερίᾳ γνώμῃ καθάπερ οἱ παλαιοὶ φιλόσοφοι τὰ πράγματα θεάσασθαι, παντάπασιν ὀλίγους παῖδας εὑρήσει πρὸς ἀρετὴν εὖ πεφυκότας καὶ παύσεται πάντας μὲν ἡμᾶς ἡγούμενος εὖ πεφυκέναι, διαστρέφεσθαι δ΄ ὑπὸ τῶν γονέων τε καὶ παιδαγωγῶν καὶ διδασκάλων …¹⁷¹

For if someone, who is not one of those contentious rascals, would want to observe the matter with free judgement, as the ancient philosophers did, he shall find that there are exceedingly few children naturally well disposed for virtue and he shall cease to hold that we are naturally good but perverted by our parents, guides and teachers.

tr. Singer, modified

Note that what the ancient philosophers understand so well here, is exactly the natural difference in the characters (and thus souls) of children, i.e. the insight that was presented as the starting-point of the whole argument of QAM by Galen in the beginning. In general, it is helpful to note that when Galen writes of ‘philosophers’ in a derogatory sense, he is not referring to Plato or Aristotle. That is to say: he quite consistently employs a distinction between the contemporary types and the ancients, and while he wants to distinguish himself from the former, he often, and especially in QAM, praises the latter and presents his own work as a continuation of theirs.¹⁷² Galen has no problem whatsoever with philosophy per se. On the contrary, his problem is with certain self-styled practitioners who do not meet the high standards the ancient philosophers have supposedly set, and who do not accept valid evidence when it is presented to them (for the soul’s dependence on the body for example, or for the location of the rational soul in the brain as opposed to the heart). The fact that Galen likes to distinguish himself from the philosophers of his day simply does not mean in any way that he does not consider himself a philosopher.

Lloyd makes a point comparable to that of Garcia-Ballester, although he presents it rather more carefully as a ‘suggestion’: ‘… this would mean that his contributions to the debates on the relations between the soul and body, and to moral philosophical issues, are in places subordinated to a strategic concern with the prestige and power of the doctor’.¹⁷³ No scholar will deny that Galen’s specific medical training, outlook and practice as well as his general concern with the status of medicine as a science, will deeply affect his philosophical work. However, if it turns out that all the relevant ‘places’ in which Galen supposedly subordinates his own philosophical aspirations to the ‘prestige and power of the doctor’ are those places in which he expresses what is considered too ‘radical’ a view on the causal role of the physical mixture, I think we have set out the contrast between medicine and philosophy too strongly and have denied Galen the possibility of an empirically and practically informed philosophy in which the body plays a crucial role. I would rather suggest that Galen works out a doctrine of the soul in which the care for the body has some ethical purport and that he presents ‘the ancients’ as proponents of this view (whether justifiedly so or not). Thus, he places himself in what he sees as the tradition of the ancient Pythagoreans and Platonists, rather than indicating a conflicting view of the value of philosophy and medicine for the health of the soul. Lloyd is only able to make this suggestion of a strategic concern with the prestige of the doctor, under the assumption that Galen works from an opposition between doctor and philosopher in QAM and affiliates himself solely with the former role. I think that Galen is not so much concerned with the power of the doctor here as with the power of the body.

Lloyd also makes a sharp distinction between ‘citation of authority’ and Galen’s ‘own independent observation’ and claims that the balance in QAM is ‘weighted very heavily towards the former’. This is another way to neutralize the apparent radicalism of QAM (because it reduces its status), and it also one that is found in some of the other scholars mentioned. I think this is a seriously problematic general distinction, especially for a writer in Galen’s age. How unusual is it for ancient writers, including Galen (in PHP, for example), to present their own views and observations under the veil of a specific and indeed sometimes rather unorthodox interpretation of more ancient authorities? Often, the whole point with this kind of writing is to blur the neat difference Lloyd is making. Besides, one might also infer that Galen, precisely because he knew his contemporaries might consider the views he expounded in QAM to be radical, purposely and emphatically tried to present them as being in line with traditional authority.

Donini follows Garcia-Ballester and Lloyd, in stating that Galen was mainly occupied with making propaganda for the office of doctor in this ‘pamphlet’, as he calls QAM (PHP on the other hand is a ‘great treatise’).¹⁷⁴ His general suggestion is that we should not take QAM as seriously as other work (Galen is speaking at a ‘different, indeed considerably lower, level than that of PHP’).¹⁷⁵ As long as we consider QAM a ‘more or less propagandizing manifesto devoted principally to promoting the image and the office of the doctor … the threatened contradictions with respect to Galen’s other works disappear’. This is a way for Donini to render ‘the thesis of the corporeal nature of the soul itself … more understandable’.¹⁷⁶ Here Donini, in my opinion, makes the same mistake as Garcia-Ballester and Lloyd. To back the hypothesis of QAM as a propagandizing pamphlet for the office of doctor, Donini also cites one single passage (IV 807–8 K), which is supposed to introduce ‘a further thesis, apparently completely novel’, namely, the thesis that one should ‘look to doctors rather than philosophers’ in order to develop one’s soul. But in this passage, Galen merely states that he is able to help those people that do not believe in the power of nourishment to develop their souls. Again, the whole opposition between doctor and philosopher is completely projected into the text on the basis of the presupposition that Galen here should be considered solely as a doctor and as such as opposed to a philosopher (again, QAM was classed by Galen as a work treating of Platonic philosophy). Galen even goes on to state that by coming to him, these people ‘will greatly enjoy the benefit of ethical philosophy’.¹⁷⁷ That is to say, he explicitly calls this care for the body philosophy. Again, right at the very beginning of QAM, it is the followers of Pythagoras and Plato whom Galen mentions as having actually lived in accordance with the views he expounds in QAM. Rather than opposing medicine to philosophy and declaring the superiority of the former, Galen attempts to integrate both fields, as he does in other work as well. And that is not even such an exceptional activity in Galen’s time, after all: Plutarch, for example, states at the beginning of Advice about keeping well, that philosophers should ‘make a single field, as it were, of all honourable studies’, among which he mentions medicine as ‘inferior to none’.¹⁷⁸ Again, the fact that Galen is a doctor and advocate of the medical science strongly and directly influences his thinking and writing to an extent that is not to be underestimated. However, to explain his supposedly ‘extreme’ or ‘radical’ views on the soul in terms of a kind of power-play between doctor and philosopher, seems to not do justice to Galen’s self-understanding as both a doctor and philosopher and to his constructive and intensive relation towards philosophy (let us not forget here that Galen literally wrote dozens of philosophical works, including commentaries on and polemics with all the major philosophical schools, he is never merely a doctor positioning himself over against philosophy as a field of which he himself is not part in some way).¹⁷⁹ What the above-mentioned scholars seem to have in common is that they oblige themselves to come up with some explanation for the conclusions Galen presents in QAM other than the one that seems to lie most at hand. Namely that they are, in the first place, expressions of Galen’s own thought. I think part of the reason to desire such an explanation, besides the assumed contradictions with other work discussed above, is the supposition that these conclusions are ‘radical’ or ‘extreme’ (see the various citations throughout this section). I also think it may be an unfruitful interpretational strategy to judge an author’s position as radical or extreme first, and then ask what could possibly be the reason for such radicalism, now assuming that the views, being radical, cannot simply be the author’s views but came to be in his text for some other reason. Quite apart from that, the position presented in QAM does not strike me as radical at all. In any case, I think it may be worth our while to see what the implications of this position are according to Galen himself, when it comes to those beautiful fruits of philosophy. In the final paragraph of this first case-study, we shall work out some of these implications and see how QAM’s ‘physicalist’ notion of the soul bears on the possibility of ethics.