In this careful study of the fragments of Parmenides' hexameter poem, ""On Nature,"" Alexander P. D. Mourelatos combines traditional philological reconstruction with the approaches of literary criticism and philosophical analysis to reveal the thought structure and expressive unity of the best preserved, most important and coherent text of Greek philosophy before Plato. The author shows how Parmenides' deduction of the ""signposts"" and ""bounds"" of ""what-is"" critically defines the concept of reality implicit in Greek-cognitive vocabulary and in early speculative cosmologies. He interprets the second part of the poem, the ""Doxa,"" as a cosmology designed to bring out both similarities and contrasts with Parmenides' own doctrine of ""what-is."" The ""Doxa"" thus serves as a semantic commentary on the first part, the ""Truth."" Mourelatos' discussions of the concepts of ""persuasion,"" ""fidelity,"" ""opinion,"" ""belief,"" and ""appearance"" elucidate terms strategically important for interpreting Parmenides and contribute in the history of Greek philosophical vocabulary. This first-time in paperback edition includes a new Introduction by the author. Also included are three essays by him, as well as one previously unpublished paper by Gregory Vlastos. (The Route of Parmenides was first published in hardcover in 1970 by Yale University Press.)