Nicholas Denyer 
Language, Thought and Falsehood in Ancient Greek Philosophy [PDF ebook] 

This book, originally published in 1991, sets forth the assumptions about thought and language that made falsehood seem so problematic to Plato and his contemporaries, and expounds the solution that Plato finally reached in the Sophist. Free from untranslated Greek, the book is accessible to all studying ancient Greek philosophy. As a well-documented case study of a definitive advance in logic, metaphysics and epistemology, the book will also appeal to philosophers generally.