Parmenides may be called the founding father of western philosophy. His poem on the unshaken heart of well-rounded-truth and the opinions of mortals contains such astonishing depth of thought that Plato, choosing Homeric epithets, called him reverend and awful (Theaetetus, 183e).Hermann Diels (1848-1922) produced the first critical edition of the poem. His edition, though a landmark of scholarship, has long been out of print. Walter Burkert has written a new preface for this reprint; and Diels' bibliography has been modernized by Daniela de Cecco.