Parmenides

Parmenides chose an unusual form for philosophy that would ordinarily be argued in prose: a poem in dactylic hexameter, the meter of epic verse, describing a young man carried by chariot beyond the gates of night and day to meet an unnamed goddess who reveals to him the difference between the Way of Truth and the deceptive Way of Opinion that mortals mistake for knowledge. What the goddess tells him is that only what is can be spoken or thought of at all, that what is not cannot even be conceived, and that it follows from this that what is cannot have come into being, since it would have had to arise from what is not, cannot pass away for the same reason, cannot be divided into separate parts, and cannot change, since change would mean something that is becoming something it currently is not. The ordinary world of birth, decay, motion, and plurality that the senses report is, on this argument, not a reliable guide to what really is at all. That conclusion forced every Greek philosopher who came after him to answer it somehow: the atomists posited indivisible unchanging atoms moving through void to preserve a Parmenidean bedrock beneath apparent change, and Plato's theory of unchanging Forms behind the changing world of appearances answers the same challenge in a different register. His student Zeno of Elea defended the same one-ness with paradoxes about motion, including the famous case of Achilles unable to overtake a tortoise, that remain live problems in the philosophy of mathematics today.

This article records tradition as it has been passed down and reported. Its sources are not yet part of the atlas's verified catalogue.

Beyond his own poem, Parmenides survives in the philosophical tradition as a character in someone else's work: Plato wrote a dialogue named simply Parmenides, staging an aged Parmenides, accompanied by his student Zeno of Elea, in conversation with a young Socrates in Athens. In Plato's telling, Parmenides subjects Socrates's early theory that abstract Forms exist separately from the particular things that share in them to a demanding series of objections, difficulties later philosophy has continued to call the problem of participation, before the dialogue moves into an intricate exercise in dialectical argument about the nature of unity itself.

Whether the meeting Plato depicts, and even Parmenides's visit to Athens, ever actually happened is a question ancient and modern scholars alike cannot settle from independent evidence, since Plato's dialogues regularly place historical figures in scenes built for philosophical purposes rather than historical record, and no other surviving source confirms the encounter. Parmenides's own biography beyond his likely birth date around 515 BCE in Elea is similarly thin: no death date for him survives in any ancient record at all, leaving the end of his life, unlike its beginning, entirely undated.

That the fullest surviving portrait of Parmenides in conversation was composed by Plato, a philosopher writing a century after Parmenides's own likely lifetime, for reasons of his own philosophical argument, says as much about how classical philosophy transmits its founding figures as it does about Parmenides himself.