Aristotle's Argument for a Human Function

A generally ignored feature of Aristotle’s famous function argument is its reliance on the claim that practitioners of the crafts (technai) have functions: but this claim does important work. Aristotle is pointing to the fact that we judge everyday rational agency and agents by norms which are independent of their contingent desires: a good doctor is not just one who happens to achieve his personal goals through his work. But, Aristotle argues, such norms can only be binding on individuals if human rational agency as such is governed by objective teleological norms.
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