Hylomorphic virtue: cosmology, embryology, and moral development in Aristotle

Abstract

Aristotle is traditionally read as dividing animal souls into three parts (nutritive, perceptive, and thinking), while dividing human souls into four parts (a rational part, with theoretical and practical subparts, and non-rational part, with nutritive and desiderative subparts). But careful reading of Nicomachean Ethics 1.13 suggests that he divides the human soul into three parts – the nutritive, the theoretical, and the “practical” – but allows that the “practical” part is sometimes divided, as in akratic and other non-virtuous agents. In a fully virtuous agent, practical reason is the proper form of – and so in the hylomorphic sense one with – the desiring part of soul. It is thus contingent how many parts a given soul has, three being the norm, but four being common. Reading Aristotle this way is supported by appeal to his cosmology, where the superlunary world provides the unitary norm, and his embryology, where male offspring are the norm (in which menstrual fluid is fully mastered by the male principle) but female offspring commonly occur when the menstrual fluid (analogous to desire) is only partially mastered by the male principle (analogous to practical reason).