Aristotle on the order of embryonic development and the homonymy principle

In Aristotle’s view, embryogenesis is the process whereby organisms are formed from uniform, unorganised matter. Further, during embryogenesis, the parts of organisms come into being consecutively, i. e. not at the same time, and their progressive formation follows a fixed order. In this paper, I shall deal with Aristotle’s account of the order of embryonic development. In particular, I shall focus on what this account can tell us about the causal factors whereby embryogenesis unfolds. I shall suggest that Aristotle’s account of the order of embryogenesis and the causal factors involved in it is mainly the solution to problems stemming from the homonymy principle: it is aimed at ensuring that, in each phase of their progressive formation, the embryo and its parts are essentially (i.e. non-homonymously) what they are. Further, I shall suggest that, in light of Aristotle’s account of the order of embryogenesis and the causal factors involved in it, we need a substantial revision of one of the most popular interpretations of Aristotle’s embryology, the interpretation according to which embryonic development is due to a potential for form (or a programme).