I lay out the charge of the “Socratic fallacy” as originally presented in Peter Geach’s 1966 paper, and discuss more recent presentations of the challenge in the form of the "Priority of Definition" principle. I advance the thesis that Plato’s Socrates is primarily committed to a methodological principle (not an epistemological one), the Principle of Controversy. Further, I identify two attendant assumptions (M and E) that are background commitments for Plato’s Socrates. Together these explain some of the inconsistencies or tensions some commentators have suggested in early platonic epistemology, and encapsulate the method and interests of the Socrates we see in the definitional dialogues.