This article responds to Laura A. Marshall’s argument that Socrates does not compare himself to a gadfly in Plato’s Apology but rather to a spur on the side of a horse directed by Apollo. In revisiting the evidence for the canonical reading, this article argues that ‘gadfly’ or some other irritant insect is the only plausible translation for μύωψ in the Apology. Scrutinizing the source of the contemporary notion of the Western philosopher is pressingly important—not only for its own sake, but because the ‘spur reading’ has made its way into public circles and even the Cambridge Greek Lexicon.