For an Aristotelian observer, the halo is a puzzling phenomenon since it is apparently sublunary, and yet perfectly circular. This paper studies Aristotle's explanation of the halo in Meteorology III 2-3 as an optical illusion, as opposed to a substantial thing (like a cloud), as was thought by his predecessors and even many successors. Aristotle's explanation follows the method of explanation of the Posterior Analytics for "subordinate" or "mixed" mathematical-physical sciences. The accompanying diagram described by Aristotle is one of the (...) earliest lettered geometrical diagrams, in particular of a terrestrial phenomenon, and versions of it can still be found in modern textbooks on meteorological optics. (shrink)

In this paper I propose to show: 1) that in Phys. II 8 Aristotle takes Empedocles as a paradigm for a theoretical position common to all philosophers who preceded him: the view that materialism implies a mechanistic explanation of natural becoming; and 2) that, since Empe­docles is regarded as a philosopher who clearly expresses the position of all mechanistic materialists, Aristotle builds his teleological arguments precisely to refute him. Indeed, Aristotle believes that refuting the argu­ments of Empedocles – the champion (...) of mechanism – means refut­ing the mechanistic theory itself. In order to illustrate this point, I will discuss some passages from Phys. II 8, while also turning to consider the Neoplatonic commentators on Aristotle’s Physics. I will then endeav­our to explain why in 198b19 ff. Aristotle formulates the argument of rain, which has attracted so much attention from scholars of the Phys­ics: I will consider whether Aristotle believes that rain serves a purpose, contrary to what he claims with regard to meteorological phenomena in Meteorologica. (shrink)