Parmenides

Parmenides of Elea, who flourished in the late sixth or early fifth century BC, was a pre-Socratic Greek philosopher from Elea in Magna Graecia, born to a wealthy and illustrious family; his exact birth year is uncertain, with estimates ranging from around 540 to 515 BC, and he is thought to have been in his prime around 475 BC. His single known work is a philosophical poem, often called On Nature, of which only fragments survive, though its integrity is remarkably higher than that of almost all other pre-Socratic writings, allowing classicists to reconstruct his doctrines with unusual precision. The poem prescribes two views of reality: the way of Aletheia, or truth, describing how all reality is one, change is impossible and existence is timeless and uniform, and the way of Doxa, or opinion, describing the world of appearances in which the senses lead to false and deceitful conceptions. Parmenides has been considered the founder of ontology and, through his influence on Plato, has shaped the whole history of Western philosophy; he is also considered the founder of the Eleatic school, which included Zeno of Elea and Melissus of Samos, and Zeno's paradoxes of motion were developed to defend Parmenides's views. His work remains relevant in contemporary debates about the philosophy of time.