Parmenides of Elea was born approximately in 515 BCE in Elea, Italy. He died sometime around the year 450 BCE, though the place of his death is unknown. He was a Greek philosopher.
Not much is known about the life of Parmenides. He is often considered the founder of the Eleatic School, and it is assumed that both Zeno of Elea and Melissus of Samos were among his students, and that he himself was the pupil of Xenophanes. Parmenides was also a, albeit, younger, contemporary of Heraclitus, whose philosophy was radically opposed to that of Parmenides. Briefly, the main distinction is that Heraclitus affirms becoming, while Parmenides argues that such becoming (or change as such) is nothing but an appearance. Due to his conviction that there is only one essence (namely Being, a single and unchangeable whole) Parmenides is sometimes referred to as a “monist.”
Parmenides is believed to have composed only one work, a poem entitled Peri physeōs (On Nature), which, examining the question of Being, had an enormous impact on earlier Greek philosophy. Only nineteen fragments (or about one hundred and sixty lines) have survived, which is mostly due to Sextus Empiricus, who copied almost all the fragments, and Simplicius, who in his commentaries on Aristotle cited great parts of the poem. The poem was originally divided into three parts: a Prelude; The Way of Truth (“aletheia”); and The Way of Opinion (“doxa”).
In the introduction, Parmenides describes a journey from the dark to the light. Carried in a chariot, the narrator, a young man, eventually meets a goddess: “The steeds that bear me carried me as far as ever my heart desired, since they brought me and set me on the renowned way of the goddess [….] There are the gates of the ways of Night and Day, fitted above with a lintel and below with a threshold of stone. They themselves, high in the air, are closed by mighty doors, and avenging Justice keeps the keys that open them.”
The elucidations of the goddess, wherein she enlightens him on what is truth, compose the rest of the work. The narrator is requested to
learn all things, as well the unshaken heart of persuasive truth, as the opinions of mortals in which is no true belief at all. Yet none the less shalt thou learn of these things also, since thou must judge approvedly of the things that seem to men as thou goest through all things in thy journey.
The second, and main part of the poem deals with what is real: with that which is and with that which is not. Affirming that there are “only two ways of search that can be thought of,” it commences with a clear duality, namely the one between truth and the one that cannot even be known.
The first, namely, that It is, and that it is impossible for anything not to be, is the way of conviction, for truth is its companion. The other, namely, that It is not, and that something must needs not be, - that, I tell thee, is a wholly untrustworthy path. For you cannot know what is not - that is impossible - nor utter it; for it is the same thing that can be thought and that can be.
The “truth” thus proposed by Parmenides’ goddess is that only what is is (true), and “what is not” is not and cannot be. What is is eternal, as it cannot become, and what is cannot be destroyed, as there is nothing outside of it. As it is “impossible for anything not to be,” change, that is taking place in this nothing, is impossible. For one cannot know nor utter what is not, not-being can neither be nor be thought.
Being indestructible, complete, changeless, and immovable, only the path of being can be known. “What is” is timeless. From this Parmenides concludes that there is no time that was outside the whole and immovable present. Future, therefore, is impossible; nothing comes into being. If being becomes, being, therefore, is not. “What is” is everywhere and remains the same, though it is also confined within the limits; “what is” is not infinite, as it needs nothing.
Of the third part the least fragments survived. It is here where Parmenides divides between the “real” and the “opinions” of men, and it is here where he grants plurality an existence within unity. This is first and foremost reflected in the last lines. In recapitulation of the poem, Parmenides yet again accounts for the men’s erroneous belief in becoming, which, just as passing, is to be seen as mere appearance:
Thus, according to men’s opinions, did things come into being, and thus they are now. In time (they think) they will grow up and pass away.
Thus in order that “no mortal may surpass thee in knowledge” the narrator is first told to learn about the fallacious sentiments of mortals and how things appear to them. Men, the goddess states, distinguish between two forms, “one of which they should have left out, and that is where they go astray from the truth. They have assigned an opposite substance to each, and marks distinct from one another. To the one they allot the fire of heaven, light, thin, in every direction the same as itself, but not the same as the other. The other is opposite to it, dark night, a compact and heavy body.”
But now that “all things have been named light and night,” Parmenides gives evidence of his conviction that they are not (to be) separated. There is only one single, unchangeable whole, which at the same time contains light and dark, “everything is full at once of light and dark night, both equal, since neither has aught to do with the other.”
Parmenides then elaborates on his cosmology, of which not much is known. In view of his conviction that nothing becomes but that everything always already is it seems interesting that he apparently negates a creation ex nihilo. In contrast, the narrator is told about the “origin of all the things,” namely how “the earth, and the sun, and the moon, and the sky that is common to all, and the Milky Way, and the outermost Olympos, and the burning might of the stars arose.” According to Parmenides, the cosmos consists of circles, of both light and dark: “The narrower circles are filled with unmixed fire, and those surrounding them with night, and in the midst of these rushes their portion of fire.” In “the midst of these circles” however, there is a female divinity that “directs the course of all things; for she rules over all painful birth and all begetting, driving the female to the embrace of the male, and the male to that of the female.” From her everything emerges, Eros being the “first of all the gods she contrived.” More on the cosmology seems to follow, yet those presumed fragments of Parmenides’ discourse have not been found.
Despite the fact that there has only been a limited number of fragments recovered and that there is not any unified agreement on how to interpret Parmenides’ work, it is evident that his influence on Western thought is paramount and he is considered one of the most important pre-Socratics. In addition to Plato, whom Parmenides had an enormous influence on, so much so that Plato named a dialogue after him, it is said that his work has also had a certain impact on Empedocles as well as on earlier atomists such as Democritus and Leucippus.