The Parthenon and Liberal Education seeks to restore the study of mathematics to its original place of prominence in the liberal arts. To build this case, Geoff Lehman and Michael Weinman turn to Philolaus, a near contemporary of Socrates. The authors demonstrate the influence of his work involving number theory, astronomy, and harmonics on Plato’s Republic and Timaeus, and outline its resonance with the program of study in the early Academy and with the architecture of the Parthenon.