Metaphysics in Aristotle's Embryology

Abstract

Traditionally, discussion of Aristotle's metaphysics, including his theory of form and the ‘what it is to be’ any given substantial object, has dealt extensively with relevant texts in the Categories, Physics, De anima and, of course, the Metaphysics itself. But the biological works have been largely neglected as sources for knowledge about and insight into Aristotle's theory. This seems to me unfortunate. In his biological works Aristotle invokes the form of an animal constantly and in interesting physical and, one would have said, metaphysical detail, as the explanation for much, and that the crucial part, of what happens to it as it develops to maturity and maintains and reproduces itself. One would expect these explanations to reveal something about the character of Aristotelian forms and perhaps even to help resolve some of the many questions not clearly settled by him in his metaphysical writings. It might, I suppose, be argued, on the contrary, that Aristotle thought that the notion of form needed for metaphysical purposes is quite distinct from that needed in order to explain the biological phenomena addressed in the Parts and the Generation of Animals. Conceivably there is no, or only a very loose, systematic connection between what is said about forms in the two sets of works, so that one is not entitled to infer metaphysical consequences – consequences for the nature of forms as they appear and are argued about on metaphysical terrain – from what forms are taken to be like in the biological context. I will not attempt to argue against this line of interpretation here. In the belief that the philosophical interest of doing so will be sufficient justification, I will simply proceed on the natural assumption that Aristotle did intend his biological theory of forms to be a continuous development and extension of whatever theory of substantial forms he meant to be the upshot of his discussion in the central books of the Metaphysics.