Parmenides (pärmĕnˈĭdēz) [key], b. c.515 B.C., Greek philosopher of Elea, leading figure of the Eleatic school. Parmenides' great contribution to philosophy was the method of reasoned proof for assertions. Parmenides began his argument with the assertion that being is the material substance of which the universe is composed and argued that it was the sole and eternal reality. With this as a premise he proceeded to destroy by his dialectic argument the possibility of generation, destruction, change, and motion. All change and motion are illusions of the senses. Since being is spatially extended and is all that exists, there is no empty space, and motion is therefore impossible. Only fragments of his work have survived.
See Parmenides (text, tr., commentary, and critical essays by L. Tarán, 1965); study by A. P. Mourelatos (1970).
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