Aristotle on Eggs

Abstract

A key issue for commentators on Aristotle’s embryology is the problem of “wind-eggs,” unfertilized eggs produced by some female birds or fish without male insemination, to which Aristotle assigns some degree of soul in Generation of Animals (GA) 2.5: nutritive soul in potentiality, which allows them to grow. This seemingly contradicts his hylomorphic doctrine that the male provides the form or soul to the new animal being generated, by providing the moving cause of generation, whereas the female provides the matter, the material cause. This dissertation argues that when Aristotle’s comments on wind-eggs are placed in the context of his account of how egg-laying animals reproduce, they do not contradict his commitment to the view that only the male animal can initiate new life (by serving as the moving cause that initiates the actualization of form in the matter). The dissertation reconstructs Aristotle’s account of oviparous generation from GA 3, showing that he distinguishes between the production of an egg and the subsequent conception of the embryo that develops inside the egg. Eggs are uterus-analogues for Aristotle; I argue that this means they should in fact be understood as parts of the animal who lays them. Following Aristotle’s functional view of body parts, we can understand him to attribute soul to wind-eggs not because they are early, defective embryos, but because they are parts of an ensouled whole, potentially able to perform a reproductive function for the egg-layer. Aristotle’s hylomorphic theory of generation presented in the rest of GA is therefore not destabilized by his comments on wind-eggs, and his association of the male with soul and activity and the female with matter and passivity remains in place. One upshot of this interpretation of wind-eggs is that it reveals how Aristotle’s mereology can allow for living wholes to have physically disconnected parts that still share in the life of the whole for a time. Correspondingly, we see how the generation of egg-laying animals is a less physically unified process than that of live-bearing animals, reflecting one way that Aristotle’s hierarchy of living beings comes into play in his biological thought.