Parmenides of Elea (; ; fl. late sixth or early fifth century BCE) was a
pre-Socratic Greek philosopher from
Elea in
Magna Graecia (Greater Greece, included Southern Italy). He was the founder of the
Eleatic school of
philosophy. The single known work of Parmenides is a
poem,
On Nature, which has survived only in fragmentary form. In this poem, Parmenides describes two views of
reality. In "the way of truth" (a part of the poem), he explains how reality (coined as "what-is") is one,
change is impossible, and
existence is timeless, uniform, necessary, and unchanging. In "the way of opinion," he explains the world of appearances, in which one's sensory faculties lead to conceptions which are false and deceitful. These ideas had a strong effect on
Plato, and in turn, influenced the whole of
Western philosophy.