This article is the first to focus on statements about ethical guidance in post-classical astronomy texts. A number of astronomers in post-classical Islamic societies remarked that the study of astronomy, specifically the mathematical analysis of the uniform motions of the celestial orbs, had ethical benefits. These astronomers’ statements are significant because, through them, scholars can learn more about the role of reason in Islamic thought and about sources of ethical guidance other than Sharīʿa and philosophical ethics. The details of the ethical guidance imparted by the study of astronomy tell us more about the relationship between astronomy and the disciplines of fiqh and kalām, respectively. The existence of ethical guidance in astronomy texts is additional evidence that post-classical astronomy texts were part of an Islamic intellectual tradition.
Although overshadowed by his celebrated commentaries on Ibn ʿArabī and Ibn al-Fāriḍ, Dāwūd al-Qayṣarī’s (d. 750/1351) treatise on the philosophy of time – the Nihāyat al-bayān fī dirāyat al-zamān (The Utmost Elucidation Concerning Knowledge of Time) – is a notable milestone in the history of Islamic conceptions of temporality. Composed around the start of Qayṣarī’s tenure as head of the first Ottoman madrasa, the Nihāyat al-bayān rejects the Aristotelian definition of time as the number of motion in favor of Abū l-Barakāt al-Baghdādī’s concept of zamān as the measure of being. Challenging, likewise, portrayals of time as a flux or succession of fleeting instants, Qayṣarī propounds instead an absolutist vision of time as an integral, objectively existent whole. Qayṣarī’s reassessment of dominant medieval theories of temporality – including kalām atomism and the Neoplatonic distinction between time, perpetuity, and eternity – is thus shown to be a key early example of what was to become an abiding Ottoman interest in time and timekeeping.
The principle known as the possibility of the nobler (qāʿidat imkān al-ashraf) is arguably one of the most often employed principles in later Islamic philosophy. In its standard formulation it states that if something baser exists, a nobler thing must have existed prior to it. A similar argument from the degrees of perfections has had a long career in the history of Western philosophy as well, with its beginnings reaching Stoicism. In Christian theology and philosophy it serves most importantly as a proof for the existence of God in the so-called henological argument of Aquinas. In Islamic philosophy it directly derives from the ex uno non fit nisi unum principle. Since the formulation of its standard version by al-Suhrawardī, the validity of the principle has been conditioned on that it is only applicable to the intelligible beings, hence its main objective is to offer a proof for the existence of the intellects. The article analyzes the application of the principle in Ṣadrā’s philosophy and enquires about its historical roots.