Kant’s Transcendental Deduction of the Categories, written by Kenneth R. Westphal

In: History of Philosophy & Logical Analysis
Lara Scaglia Philosophy, University of Warsaw Warsaw Poland

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Kenneth R. Westphal. 2021. Kant’s Transcendental Deduction of the Categories. Helsinki: Helsinki University Press. ISBN: 9789523690288 (paperback); 9789523690295 (pdf); 111 pages. DOI: 10.33134/HUP-7

After Kant’s Transcendental Proof of Realism (2004) and Kant’s Critical Epistemology: Why Epistemology Must Put Judgment First (2020) Kenneth R. Westphal offers once again an insightful book on Kant. This time, the author aims to fulfil his interpretive tasks opened in his previous books and leave behind Kant’s transcendental idealism, by identifying Kant’s reasons, proof and key issues in the Deduction and providing a fresh translation of some passages of it.

Before delving into the content of this third book, I would like to briefly recall the main goals and outcomes of the previous books, with which this last work is closely related. In Kant’s Transcendental Proof of Realism, Westphal claims that Kant must presuppose that the contents of the sensory manifold are associable and that therefore a transcendental material condition of experience must be admitted. The synthetic unity of apperception, through which the subject can grasp a manifold of sensible representations as belonging together in a particular perception, is the condition for the analytic unity through which such perception can belong to the subject’s experience. In this way, the unity of the conscious experience is dependent on the transcendental affinity, which for Westphal must be something given and not a function of the constitutive activity of the “I”, for otherwise one would have to admit that Kant suggests a material idealism in which not only the form but also the matter of appearances is constituted by the subject. The consequence of this claim about the transcendental material condition of experience, of course, is the failure of Kant’s transcendental idealism: objects, within this view, have spatial features and only because of these characteristics they possess the conditions for being substances – engaged in external causal relations – and for being objects of our forms of intuition.

In the second book, Kant’s Critical Epistemology: Why Epistemology Must Put Judgment First, Westphal continues his argument for a common-sense perceptual realist interpretation of Kant’s Critique of Pure Reason. He argues that Kant defends a non-Cartesian epistemology – which leads to an internalist infallibilism – by proposing a form of externalism about the content of cognition, causal relations and cognitive justification. According to the author, we can have justified causal beliefs only on the basis of some evidence for such a causal explanation and not because of inner psychological states.

This scientific realistic approach is further developed in this third work: Kant’s Transcendental Deduction of the Categories. Critical Re-Examination, Elucidation and Corroboration. Indeed, the author is convinced that transcendental idealism can and should be left behind because Kant’s Deduction does not address ontological problems but only issues of validity that are neutral and independent from transcendental idealism. More specifically, Westphal recognises that the main points of the Deduction concern mostly cognitive semantics: the Deduction refers to necessary conditions required to think so as to be able to identify particulars and to ascribe features to them. Therefore, it does not deal with the specification of objects, but just with the conditions through which we can be self-consciously aware of them. The book is divided into an introduction (1§), a section dedicated to basic considerations for the understanding of the Deduction (2§), the translation and elucidation of some passages from the Deduction (3§), and then two argumentative parts – followed by the analytical contents (6§) and the references (7§) – concerning the concepts space, time and the categories (4§) and the modality in sensory experience and perceptual judgement (5§).

In the second section, Westphal focuses on some basic characteristics of the Deduction. The chapter concerning the Deduction is short because Kant wants to circumscribe his issue, having already distinguished understanding and sensibility, which have two integrated but distinct roles within human cognition and experience and involve various combinations. The forms of these combinations are structured by the categories, which are called transcendental – a term used in medieval metaphysics to designate general features of all beings – because they designate a priori aspects required for all possible thoughts concerning the experience. In the first Critique, Kant deals with both the cognitive process and cognitive validity: while the subjective deduction concerns how we can have experience and judge; the objective deduction deals with the formal conditions under which it is possible to make cognitive judgements. In this way, Kant constructs a functionalist cognitive architecture – as Westphal calls it in his book of 2020.

But when we approach the Deduction, it is highly important to bear in mind the distinction between issues concerning the process and those regarding validity. In this regard, the author wants to draw the reader’s attention to unclear and sometimes misleading expressions used by Kant. For instance, ‘representation’ (‘Vorstellung’) concerns all kinds of factors regarding our cognisance from sensations to ideas; while the translation of ‘sinnliche Anschauung’ into ‘sensory intuition’ is preferable to that into ‘sensible intuition’ because ‘sensible’ might suggest sense data or impressions in a Humean sense. In contrast, Kant uses ‘sensory intuition’ to refer to the capacity to present particulars, while ‘thinking’ is the judgement of those particulars. Besides, Kant distinguishes ‘thought’ (‘Denken’), namely the logical capacity to construct logically consistent propositions, from ‘knowledge’ (‘Erkenntnis’), which requires something more, namely the indication of some particulars in space and time about which we judge and to which we ascribe some characteristics. Mere truth values, then, are not sufficient for cognition, and demonstrative reference is needed to constitute objects of experience. Westphal further explains this expression (‘constitution of object of experience’) by distinguishing two senses: on the one hand, it involves the generation of the main features of objects; on the other hand, it regards the necessary conditions that must be satisfied to be aware of objects. The first generative sense implies an account of the cognitive process, while the second, presuppositional sense concerns how one can recognise objects: it deals with validity, not with the process of constituting objects and does not require Kant’s transcendental idealism.

The third section of the book includes the text of the Deduction in the original German and in the author’s English translation. On the opposite page are elucidations and notes to help the reader interpret the passages. Since the aim of the book is to elucidate the Deduction independently of the doctrine of transcendental idealism, the author has chosen to omit passages and footnotes on transcendental idealism and self-affection (how we are aware of ourselves in the inner sense). The aim is to look at the Deduction as dealing exclusively with issues of validity, not with the process of cognition and ontology. The main editions checked by the author are Weischädel (1974) and Timmerman (1998), and all philological and typographical details have been omitted.

The fourth section consists of an essay on space, time and categories, in which Westphal addresses some queries the reader might have because he treats space and time as ‘concepts’ and discounts their transcendental idealism. Besides, he addresses accounts of kinematics by Descartes (1644), Newton (1962), Williams (1953) and Carnap (1928) to show that the trope theorist’s ideal description and Carnap’s Aufbau with respect to time cannot explain kinematics. In contrast, the strength of Kant’s epistemology is that he can identify subpersonal functions of cognition and provide judgements we can make with sufficient reliability in connection with experience in space and time.

In the fifth section, which deals with modality and perceptual judgement, Westphal engages in an intriguing comparison between Hume’s, Reid’s, Tetens’s and Kant’s accounts of perception. Opposing Hume’s theory of impression, Reid emphasises the inadequacy of Hume’s “copy theory” of impressions and ideas, and although he does not provide an alternative to it, he highlights that our failure in understanding natural regularities do not undermine their validity, thus proposing a sort of justificatory externalism. Kant, within his empirical realism, goes in the same direction as Reid, by depicting a taxonomy of perceptual factors which is modally rich, thus deepening Tetens’s doctrine (1777), who stresses that cognition requires modalities: causality, in particular, requires more than mere psychological associations can provide. For this, as the author repeatedly declares, transcendental idealism is not required. However, the reader might wonder what this actually means. Indeed, the author does not seem to have problematised what transcendental idealism means within Kant’s work, what its relation to empirical realism is (if it is a necessary one or not) and what ontological, epistemic, semantic meanings it has not only in relation to space and time but also, for instance, to things in themselves.

I will now focus on some choices of translation that can raise some concerns or questions, if compared to other translations, such as the one by Guyer & Wood in 1998. ‘Bestimmen’, ‘Bestimmung’, ‘Gedankenbestimmung’, ‘unbestimmt’ are rendered in English as ‘specifying’, ‘specification’, ‘conceptual specification’ and ‘unspecified’. As the author says, ‘determine’ (‘bestimmen’) “can mean: cause to be as it is; yet it can also mean: specify” (7). Relating to concepts, it means to make a concept more precise, to restrict it. Nevertheless, ‘Bestimmung’ and its cognates are rendered differently from ‘specify’ in some places. For instance, “bestimmter Gegenstand” (66) is rendered as “determinated object” (66); “ein bestimmter Raum” (46) as “a determinate space” (46); “bestimmte Verbindung” (44) as “determinate connection” (44); “Bestimmung aller Vorstellung” (50) as “determination of all representations” (50). Occasionally, ‘bestimmt’ is even translated as ‘destined’, as in the passage:

Unter den mancherley Begriffen aber, die das sehr vermischte Gewebe der menschlichen Erkenntnis ausmachen, gibt es einige, die auch zum reinen Gebrauch a priori (völlig unabhängig von aller Erfahrung) bestimmt sind.

Kant, Critique of Pure Reason, B118

which is rendered thus:

However, amongst the various concepts which constitute the very mixed fabric of human cognition, there are some destined to a pure use a priori (entirely independent from all experience).

Westphal 2021, 16

I agree that the term is difficult to translate into English, but for this very reason, it must be made clear at every point why the translation is better rendered with a term other than the one considered standard by the author (‘specify’). Besides, as above mentioned, “Gedankenbestimmung” (37) is rendered as “conceptual specification” (37), and “bestimmtes Denken” (40) as “specific thinking” (40), while the German term ‘Gedanken’ should be better translated as ‘thoughts’.

“Beziehung” and “sich beziehen” are translated as “connection” and “connect” respectively (e.g., 16, 18, 26). However, “Verbindung” (82) and “Verknüpfung” (84) are translated in the same way (as ‘connection’), which does not reflect in English the different nuances of the German terms. Guyer & Wood’s translation is closer to the original text, insofar as ‘connection’ is used for ‘Verknüpfung’, ‘relation’ for ‘Beziehung’ and ‘combination’ for ‘Verbindung’.

‘Erkenntnis’/‘erkennen’ are translated inconsistently: sometimes as “knowledge”/“know” (e.g., 20, 24) and other times as “cognition”/“cognize” (e.g., 26, 28, 36, 40, 76). It is not clear whether the author makes this distinction on purpose and, if so, what his reasons are.

‘Gemüth’ is a difficult term to translate. In Guyer & Wood it is rendered as ‘mind’, while Westphal uses “mentality” (20). Aware of the complexity of this notion and of the lack of an adequate translation – both ‘mind’ and ‘mentality’ might be misleading – Westphal provides an accurate and clear elucidation of the meaning of “Gemüth” (37): Kant uses it to render the Latin term animus, which identifies whatever makes a being alive and active. In this way, according to the author, Kant makes an allusion to an account of human embodiment and is able to avoid Cartesian dualism.

‘Recht’ and its cognates are rendered in several ways. For example, ‘die Frage über das, was Rechtens ist’ is ‘the question concerning justice’ and “Rechtsanspruch” (14) is “claim of justice” (14). “Rechtsgrund” (14) is “grounds of justification” (14) and “Rechtmäßigkeit” (16) is “legitimacy” (16). But the standard translation of the term, not only in Kant’s theoretical works but also in the practical ones, is ‘right’. Even if this is not the context of the philosophy of right – in which it is important to distinguish between legal and right – I believe it is better to keep the same translation. Translating, as mentioned above, ‘Rechtens’ with ‘justice’ might lead to misunderstandings: ‘Rechtens’ is in fact referred to here as the quid juris question, which does not concern justice, but accordance to rules, legitimacy in an epistemic sense.

‘Überhaupt’ is translated into “as such” (e.g., 14, 26, 30). This translation, however, makes it difficult for the reader to distinguish ‘überhaupt’ from ‘an sich’. Guyer & Wood translate it as “in general” (e.g. 219, 224,245), which is much closer to the common translation of this term into English.

Besides, I found some minor omissions and additions to the original text. For instance, the expression “Rechtshandel” (‘in a legal matter’) is omitted (16), while “erworben worden” (16) is rendered, with the addition of a modal verb, as “can be acquired” (16). The active construction “Bedingungen, deren der Verstand zur synthetischen Einheit des Denkens bedarf” (20) is translated passively as “conditions required by the understanding” (20). I agree that it is difficult to maintain a syntax which perfectly mirrors the original and that sometimes the consequence of too literal a translation is that the sentence sounds unclear in English. Nevertheless, I believe that it is better to maintain the ambiguity of some sentences or their too-much articulated syntax in order to leave the reader free to interpret them. For instance, Westphal translates the well-known passage:

Unter dem ersteren stehen alle mannigfaltige Vorstellungen der Anschauung, so fern sie uns gegeben werden, unter dem zweiten, so fern sie in einem Bewußtseyn müssen verbunden werden können; denn ohne das kann nichts dadurch gedacht oder erkannt werden, weil die gegebene Vorstellungen den Actus der Apperception: Ich denke, nicht gemein haben und dadurch nicht in einem Selbstbewußtseyn zusammengefaßt seyn würden.

Kant, Critique of Pure Reason, B137–138


All manifold representations of intuition stand under the former, so far as they are given to us; and under the latter, so far as they must be able to be conjoined within one single consciousness; for without such conjunction nothing can be thought or cognised, because the given representations would have nothing in common with the actus of apperception.

Westphal 2021, 42–44

Although the meaning is close, I believe that Guyer & Wood’s translation (“the given representations would not have in common the act of apperception”, 246) is closer to the original one, because it does not change the accusative (the act of apperception).

Another controversial passage is found on page 68, where Westphal relates ‘in der Anschauung’ to the verb, while Guyer & Wood relate it to the noun ‘Gegenwart’. According to Westphal,

Einbildungskraft ist das Vermögen, einen Gegenstand auch ohne dessen Gegenwart in der Anschauung vorzustellen.

Kant, Critique of Pure Reason, B151

should be rendered as “The power of imagination is the capacity to represent an object in intuition even without its presence” (Westphal 2021, 68), and not as “the capacity to represent an object even without its presence in intuition” (Guyer & Wood).

Furthermore, while elucidating the notions of space and time, Westphal addresses them as “concepts” (19). It is true that in the Critique of Pure Reason space and time are addressed as “concepts” (e.g., B119, B207, B 753), but not only and not predominantly. They are, in fact, the “pure forms of sensible intuition” (e.g., B36, B305) and function as “formal intuition” (B161). In the fourth section, Westphal addresses this query and distinguishes between distinctive roles of the use of the concepts of space, spaces (regions within space), time and times (periods within time) in relation to the forms of sensory receptivity. However, the explanation leads to further questions (concerning, for instance, the schematism and the notion of formal intuition) and perhaps it would have been better to preface the text with this clarification or to include it in the explanations to make it easier for the reader to deal with this issue.

To conclude, I appreciate Westphal’s challenge to engage with the Deduction in fresh ways. Still, I think it is better to stay as close as possible to the original structure of the text and perhaps include the German words when they are translated in different ways. In this way, it is possible to avoid steering the reader in what is only one possible direction of interpretation. This can be said from a broader perspective, too: Westphal omits several passages from the Deduction because they refer to what he calls matters of process or concern transcendental idealism. This operation is for sure intriguing, challenging and very helpful in approaching Kant from an analytical approach. But the impression that some readers might have is that the author does not prove that we can make use of the Deduction disregarding transcendental idealism, but at best that if we admit that transcendental idealism can be left behind, the Deduction still holds epistemological value.

More specifically, Westphal claims that the Deduction is neutral with respect to the transcendental-idealist account of space and time as forms of human sensibility: it is only through the use of the understanding in the judgement that categories can be applied to objects in intuition “as such”, regardless of the type of sensible intuition (67). Again, if one considers only the text provided by Westphal, it can be easy to sympathize with such a claim.

However, this becomes much more troublesome when we compare Westphal’s thesis of the independence of the Deduction from the transcendental idealism of space and time with claims concerning the figurative synthesis and the relation between understanding and inner sense (the form of which is time). Without having to delve into the schematism chapter, Kant already establishes the necessary relation between understanding and inner sense in the Deduction. In the act of thinking, reference to the inner sense and its pure form, time, is needed. To put it in Kant’s words, determinate intuition

[…] is possible only through the consciousness of the determination of the manifold through the transcendental activities of the imagination (synthetic influence of the understanding on the inner sense), which I have named the figurative synthesis. […] The understanding, therefore, does not find some sort of combination of the manifold already in inner sense, but produces it, by affecting inner sense.

Kant, Critique of Pure Reason, B154–155

Now, the figurative synthesis carried out by the imagination rests on the laws of the understanding (B150–152), and then there seems to be no room for an independentist thesis, namely, for leaving open the question of whether particulars can be experienced without the categories.

These points of criticism aside, I am convinced that the book is didactic and challenging: it allows the reader to read the Deduction in a fresh way – which is quite an enterprise! – and provides solid grounds for engaging in a debate with analytic philosophers.


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