This chapter offers a fresh account of Aristotle's contribution to the long debate in antiquity among philosophers, rhetoricians and medical writers concerning the relative merits, or demerits, of accumulated experience (empeiria) and of theoretical know-how (technê) as powers for successful practical action. In pursuing this topic, Bolton offers an extensive investigation of the relation between the account of these powers offered by Aristotle in Metaphysics I.1 and that found in the Nicomachean Ethics. He carefully distinguishes the different notion of universal that are available to Aristotle in characterizing the object of technê, arguing that the notion of universal underlying Aristotle’s account of technê in Metaphysics I.1 is the one we find in the Posterior Analytics, thereby giving us a theoretically flavoured notion of technê. However, this notion is not generally presupposed by the accounts we find elsewhere in the Aristotelian corpus. Particularly, in the Topics a different conception of technê emerges as empeiria or experience, an account which coincides with those defended by the later medical empiricists.