Parmenides of Elea was a Presocratic Greek philosopher. As the first philosopher to inquire into the nature of existence itself, he is incontrovertibly credited as the “Father of Metaphysics.” Parmenides’ only written work is a poem entitled, supposedly, but likely erroneously, On Nature. Only a limited number of “fragments” (more precisely, quotations by later authors) of his poem are still in existence, which have traditionally been assigned to three main sections—Proem, Reality (Alétheia), and Opinion (Doxa).

The Proem (prelude) features a young man on a cosmic (perhaps spiritual) journey in search of enlightenment, expressed in traditional Greek religious motifs and geography. This is followed by the central, most philosophically-oriented section (Reality). Here, Parmenides positively endorses certain epistemic guidelines for inquiry, which he then uses to argue for his famous metaphysical claims—that “what is” (whatever is referred to by the word “this”) cannot be in motion, change, come-to-be, perish, lack uniformity, and so forth.

The final section (Opinion) concludes the poem with a theogonical and cosmogonical account of the world, which paradoxically employs the very phenomena (motion, change, and so forth) that Reality seems to have denied. Furthermore, despite making apparently true claims (for example, the moon gets its light from the sun), the account offered in Opinion is supposed to be representative of the mistaken “opinions of mortals,” and thus is to be rejected on some level. 'd like to share some of those framents today.

"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, who with her own hands conducts the man
who knows through all things. On what way was I borne along; 

For on it did the wise steeds carry me, drawing my car,
and maidens showed the way. And the axle, glowing in the socket -
for it was urged round by the whirling wheels at each
end - gave forth a sound as of a pipe, when the daughters of the
Sun, hasting to convey me into the light, threw back their veils

...from off their faces and left the abode of Night.
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. 

Her did the maidens entreat with gentle words and skilfully persuade
to unfasten without demur the bolted bars from the gates.
Then, when the doors were thrown back,
they disclosed a widepening, when their brazen
hinges swung backwards in the sockets fastened with rivets and nails. 

Straight through them, on the broad way, 
did the maidens guide the horses and the car,
and the goddess greeted me kindly, and took my right hand
in hers, and spake to me these words: -
Welcome, noble youth, that comest to my abode on the car

...that bears thee tended by immortal charioteers! It is no ill
chance, but justice and right that has sent thee forth to travel
on this way. Far, indeed, does it lie from the beaten track of
men ! Meet it is that thou shouldst 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."