Who is Parmenides from A History of Western Philosophy and what is their importance?

Parmenides was born in Elea, Southern Italy around 450 BC. His doctrines influenced both Plato and Socrates while he himself was greatly influenced by Pythagoras. Most philosophers in this area engaged in mysticism and religion. A major influence for Parmenides was Pythagoras. He found a metaphysical argument that remains persistent in most of the subsequent philosophies until Hegel. His contribution involves the invention of metaphysics that is based on logic.