Aristotle: On the Heavens

The concept of kosmos did not play the leading role in Aristotle’s physics that it did in Pythagorean, Atomistic, Platonic, or Stoic physics. Although Aristotle greatly influenced the history of cosmology, he does not himself recognize a science of cosmology, a science taking the kosmos itself as the object of study with its own phenomena to be explained and its own principles that explain them. The term kosmos played an important role in two aspects of his predecessor’s accounts that Aristotle (...) rejected: first, cosmogeny and kosmopoiia, generation or creation of the kosmos; second, diakosmêsis, arranging of a plurality of kosmoi. Aristotle was extremely critical of accounts involving kosmopoiia and diakosmêsis and he developed general dialectical strategies against them. In emphatically distinguishing his view from all his predecessors (including Plato), he uses the terms ho ouranos (the heaven), to holon (the whole), and to pan (the totality) in preference to ho kosmos (the kosmos or world). There is usually no harm in speaking loosely of ‘Aristotle’s cosmology’ when referring to his concept of the order of nature and the ouranos. Nevertheless, Aristotle’s theoretical philosophy offers something very different from those of his predecessors for whom kosmos was a keyword. (shrink)

Attempts to find perennial elements in Aristotle’s cosmology are doomed to failure because his distinction of sub- and supra-lunary realms no longer holds. More fruitful approaches to the contemporary importance of Aristotelian cosmology must focus on parities of reasoning rather than content. This paper highlights the striking parallels between Aristotle’s use of symmetry arguments in cosmology and instances of Noether’s First Theorem in contemporary physics. Both observe simple motion, find symmetries in that motion, argue from those symmetries to notions of (...) conservation, and then conclude to cosmological structure. These parallels reveal an enduring relevance for Aristotelian cosmology that does not depend on positing an enduring content to his cosmological claims. (shrink)

Bessarion’s major philosophical treatise In Calumniatorem Platonis is a systematic approach to Platonic and Aristotelian philosophy written in response to George of Trebizond’s Comparatio Philosophorum Aristotelis et Platonis, which attacked Plato’s authority and proclaimed Aristotle’s superiority. A striking example of this is Bessarion’s attempt to defend Plato against George of Trebizond’s accusation that Plato did not offer sound arguments in favor of the immortality of the soul. In this article, I focus on Plato’s proof of the immortality of the soul (...) in the Phaedrus (245c5-246a2), as presented by Bessarion in the eighth chapter of the second book of the In Calumniatorem Platonis. The Phaedrusʼ proof is based on soul’s definition as a self-mover: since the soul always moves itself, it is the source of motion and is, therefore, ungenerated, imperishable and immortal. Bessarion’s interpretation of the Platonic proof gives the impression that Bessarion cites the text where Plato argues that the soul is immortal (245c5-9), and he summarises the text where Plato argues that the soul is ungenerated and imperishable (245d1-246a2). I argue, however, that Bessarion does not offer an original reading of the Phaedrus’ proof, and I also propose that Bessarion’s interpretation reflects his attempt to harmonize the Platonic and the Aristotelian views. (shrink)

For Aristotle, the shape of a physical body is perceptible per se (DA II.6, 418a8-9). As I read his position, shape is thus a causal power, as a physical body can affect our sense organs simply in virtue of possessing it. But this invites a challenge. If shape is an intrinsically powerful property, and indeed an intrinsically perceptible one, then why are the objects of geometrical reasoning, as such, inert and imperceptible? I here address Aristotle’s answer to that problem, focusing (...) on the version of it that he presents in De caelo III.8. I argue that if we grant that Aristotle conceived of the shape of a sensible body as some kind of causal power, then the satisfactory resolution of that challenge pushes us to interpret him as having conceived of it as being, more specifically, an impure power—that is, as a property that is not only intrinsically powerful but also, in some way, intrinsically non-powerful as well. This is a notable result not only insofar as it illuminates Aristotle’s conception of shape but also insofar as it contributes to our knowledge of Aristotle’s theory of dunameis and his ontology more broadly. (shrink)

_ Source: _Volume 60, Issue 1, pp 88 - 126 The dominant interpretation of Metaphysics Θ.8 commits Aristotle to the claim that the heavenly bodies’ eternal movements are not the exercises of capacities. Against this, I argue that these movements are the result of necessarily exercised capacities. I clarify what it is for a heavenly body to possess a nature and argue that a body’s nature cannot be a final cause unless the natural body possesses capacities that are exercised for (...) the sake of its nature qua form. This discussion yields a better understanding of what capacities are, what explanatory work capacities do, and what it is to possess a nature. (shrink)

Review of Simplicius: On Aristotle, On the Heavens 3.1-7, trans. Ian Mueller, London: Duckworth, 2009.

In this article, I examine a Latin paraphrase of Aristotle's De caelo known as the Liber celi et mundi. The text was translated from Arabic in the third quarter of the twelfth century, and thus pre-dates all four Latin translations of De caelo in the twelfth and thirteenth centuries. It was probably written by the ninth century Arab, Hunayn ibn Ishaq. I show the weakness of a previous theory that the Liber celi et mundi derives indirectly from Themistius's paraphrase of (...) De caelo. The text was translated into Latin by Dominicus Gundissalinus and his Jewish colleague, Johannes Hispanus. From c.1250, it was mis-attributed to Avicenna, and there is evidence that it had earlier been attributed to Aristotle by certain English writers. I consider the function of the Liber cell el mundi within the corpus of early Aristotelian translations, and the date of its expulsion from the corpus. (shrink)