This course will examine Aristotle's Physics as a science as conceived in the Posterior Analytics and through methodological comments within the Physics. In other words, the treatise consists of first principles i.e., hypotheses and definitions and definitions of the principle kinds (Physics II 1-2, III-V 2) and definitions of attributes (V 3), and demonstrations, including demonstrations of the essence and demonstrations in a fairly loose sense (Physics V-VIII). In addition, the text includes methodological discussions of how to investigate and the ingredients of explanations in nature, and more. It is of deep significance for understanding III-VIII that these books concern change and work at a general level (cf. Physics II 3), so that the subject is mostly treated as perceptible magnitude. Therefore, teleology is nigh absent from the discussion or present in a trivial way (a motion or the end of a motion). The treatise concludes with what I call a capstone theorem, that the first mover of everything has no magnitude. Many have looked at the Physics as involving some method of dialectical investigation through worthy opinions (endoxa); I take a different approach.