When considering the question of what makes us human, the ancient Greeks provided numerous suggestions. This book argues that the defining criterion in the Hellenic world, however, was the most obvious one: speech. It explores how it was the capacity for authoritative speech which was held to separate humans from other animals, gods from humans, men from women, Greeks from non-Greeks, citizens from slaves, and the mundane from the heroic. John Heath illustrates how Homer's epics trace the development of immature young men into adults managing speech in entirely human ways and how in Aeschylus' Oresteia only human speech can disentangle man, beast, and god. Plato's Dialogues are shown to reveal the consequences of Socratically imposed silence. With its examination of the Greek focus on speech, animalization, and status, this book offers new readings of key texts and provides significant insights into the Greek approach to understanding our world.