Abstract

At Philebus 23c4-26d10 Socrates makes a division into three kinds: Unbounded (apeiron), Bound (peras), and Mix (meikton). I review problems for the main interpretations of Unbounded and Mix and review kinds of scales defined in abstract measurement theory. Then I take 23c4-26d10 speech by speech, interpreting the Unbounded as a kind containing partial scales, Bound as the kind containing the relations and quantities needed to turn partial scales into appropriate ratio scales, and Mix as the kind containing ratio scales appropriate for the good things that come to be in the world.