A citizen of Elis, Hippias was a polymath and teacher, and is represented by Plato as a leading Sophist. He was a distinguished mathematician who probably discovered the quadratrix, the first curve other than the circle recognized in Greek mathematics. Philosophically he appears to have stood for an anti-Platonic empiricism, perhaps similar to the later standpoint of Aristotle, and he is known to have been interested in the antithesis between nature and convention.