The Timaeus-Critias is concerned with cosmology and Plato's claim that its central task is to articulate the way in which the cosmos manifests the values of goodness and beauty. This book examines this important dialogue in its entirety using current methods of Platonic scholarship. Arguing that Aristotle's physics is far closer to the Timaeus than usually realized, the study's other prominent findings reinforce the dialogue's essentially moral message, and clarify its literary character.