Parmenides of Elea (late sixth or early fifth century BC) was a pre-Socratic Greek philosopher from Elea in Magnaraecia (Greater Greece, including 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.

From a contemporary point of view, we could say that Parmenides expresses a form of non-dualistic thinking, and argues for philosophical monism. Plato calls him in the Sophist dialog the "father of philosophy."

Parmenides wrote in verse: His poem is in Homeric hexameters, and there are many Homeric images, especially from the Odyssey. In the poem Parmenides presents a young man (kouros, in Greek), who is taken in a chariot to meet a goddess. He is told by her that he will learn “all things”; moreover, while the goddess says that what the kouros is told is true, she stresses that he himself must test and assess the arguments she gives.

The poem begins with a long introduction (The Proem, B1); this is followed by a section traditionally called Truth (B2–B8.50). This is followed by the so-called Doxa section (“beliefs” or “opinions”)—a cosmology that, the goddess warns, is in some way deceptive. In Truth, Parmenides argues that genuine thought and knowledge can only be about what genuinely is (what-is), for what-is-not is literally unsayable and unthinkable. Parmenides warns against what he calls the “beliefs of mortals,” based entirely on sense experience; in these, the goddess says, “there is no true trust.” Rather, one must judge by understanding (the capacity to reason) what follows from the basic claim that what-is must be, and what-is- not cannot be. The poem proceeds (in the crucial fragment B8) to explore the features of genuine being: what-is must be whole, complete, unchanging, and one. It can neither come to be nor pass away, nor undergo any qualitative change. Only what is in this way can be grasped by thought and genuinely known.

Parmenides: On Nature

Source: Cohen, Sheldon M., et al. Readings in Ancient Greek Philosophy: From Thales to Aristotle. Hackett Publishing, 2016.

{27} 1. (28B1) The mares which carry me as far as my spirit ever aspired were escorting me, when they brought me and proceeded along the renowned route of the goddess, which brings a knowing mortal to all cities one by one. On this route I was being brought, on it wise mares were bringing me, straining the chariot, and maidens were guiding the way.

The axle in the center of the wheel was shrilling forth the bright sound of a musical pipe, ablaze, for it was being driven forward by two rounded wheels at either end, as the daughters of the Sun were hastening to escort <me> after leaving the house of Night for the light, having pushed back the veils from their heads with their hands.

There are the gates of the roads of Night and Day, and a lintel and a stone threshold contain them. High in the sky they are filled by huge doors of which avenging Justice holds the keys that fit them. The maidens beguiled her with soft words 15 and skillfully persuaded her to push back the bar for them quickly from the gates. They made a gaping gap of the doors when they opened them, swinging in turn in their sockets the bronze posts fastened with bolts and rivets. There, straight through them then, 20 the maidens held the chariot and horses on the broad road. And the goddess received me kindly, took my right hand in hers, and addressed me with these words: Young man, accompanied by immortal charioteers, who reach my house by the horses which bring you, welcome—since it was not an evil destiny that sent you forth to travel this route (for indeed it is far from the beaten path of humans), but Right and Justice. It is right that you learn all things— both the unshaken heart of well-persuasive Truth and the beliefs of mortals, in which there is no true trust. 30 But nevertheless you will learn these too—how it were right that the things that seem be reliably, being indeed, the whole of things.

(lines 1–30: Sextus Empiricus, Against the Mathematicians 7.111– 14; lines 28–32: Simplicius, Commentary on Aristotle’s On the Heavens, 557.25–558.2; )

2. (B2) But come now, I will tell you—and you, when you have heard the story, bring it safely away— which are the only routes of inquiry that are for thinking: the one, that is and that it is not possible for it not to be, is the path of Persuasion (for it attends upon Truth), the other, that it is not and that it is right that it not be, 5 this indeed I declare to you to be a path entirely unable to be investigated: For neither can you know what is not (for it is not to be accomplished) nor can you declare it. (Proclus, Commentary on Plato’s Timaeus 1.345.18; lines 3–8: Simplicius, Commentary on Aristotle’s Physics 116.28;)

3. (B3) . . . for the same thing is for thinking and for being.22 (Clement, Miscellanies 6.23; Plotinus, Enneads 5.1.8)

4. (B4) But gaze upon things which although absent are securely present to the mind. {28} For you will not cut off what-is from clinging to what-is, neither being scattered everywhere in every way in order nor being brought together. (Clement, Miscellanies 5.15)

5. (B5) . . . For me, it is indifferent from where I am to begin: for that is where I will arrive back again. (Proclus, Commentary on Plato’s Parmenides 1.708) .

6. (B6) It is right both to say and to think that it is what-is: for it can be, but nothing is not: these things I bid you to ponder. For I < 23 > you from this first route of inquiry, and then from that, on which mortals, knowing nothing, wander, two-headed: for helplessness in their 5 breasts steers their wandering mind. They are borne along deaf and blind alike, dazed, hordes without judgment for whom to be and not to be are thought to be the same and not the same, and the path of all is backward-turning. (Simplicius, Commentary on Aristotle’s Physics 86.27–28; 117.4–13;)

7. (B7) For in no way may this prevail, that things that are not are; but you, hold your thought back from this route of inquiry and do not let habit, rich in experience, compel you along this route to direct an aimless eye and an echoing ear and tongue, but judge by reasoning (logos) the much-contested 5 examination spoken by me. (lines 1–2: Plato, Sophist 242a; lines 2–6: Sextus Empiricus, Against the Mathematicians 7.114; tmpc)

8. (B8) . . . Just one story of a route is still left: that it is. On this [route] there are signs very many, that what-is is ungenerated and imperishable, a whole of a single kind, unshaken, and complete. Nor was it ever, nor will it be, since it is now, all together 5 one, holding together: For what birth will you seek out for it? How and from what did it grow? From what-is-not I will allow you neither to say nor to think: For it is not to be said or thought that it is not. What need would have roused it, later or earlier, having begun from nothing, to grow? 10 In this way it is right either fully to be or not. Nor will the force of true conviction ever permit anything to come to be beside it from what-is-not. For this reason neither coming to be nor perishing did Justice allow, loosening her shackles, but she [Justice] holds it fast. And the decision about these things is in this: 15 is or is not; and it has been decided, as is necessary, to leave the one [route] unthought of and unnamed (for it is not a true route), so that the other [route] is and is genuine. But how can what-is be hereafter? How can it come to be? For if it came to be, it is not, not even if it is sometime going to be. 20 Thus coming-to-be has been extinguished and perishing cannot be investigated. Nor is it divisible, since it is all alike, and not at all more in any way, which would keep it from holding together, {29} or at all less, but it is all full of what-is. Therefore it is all holding together; for what-is draws near to what- is. 25 But unchanging in the limits of great bonds it is without starting or ceasing, since coming-to-be and perishing have wandered very far away; and true trust drove them away. Remaining the same and in the same and by itself it lies and so remains there fixed; for mighty Necessity 30 holds it in bonds of a limit which holds it in on all sides. For this reason it is right for what-is to be not incomplete; for it is not lacking; otherwise, what-is would be in want of everything. What is for thinking is the same as that on account of which there is thought. For not without what-is, on which it depends, having been solemnly pronounced, 35 will you find thinking; for nothing else either is or will be except what-is, since precisely this is what Fate shackled to be whole and changeless. Therefore it has been named all things that mortals, persuaded that they are true, have posited both to come to be and to perish, to be and not, 40 and to change place and alter bright color. But since the limit is ultimate, it [namely, what-is] is complete from all directions like the bulk of a ball well-rounded from all sides equally matched in every way from the middle; for it is right for it to be not in any way greater or lesser than in another. 45 For neither is there what-is-not—which would stop it from reaching the same—nor is there any way in which what-is would be more than what-is in one way and in another way less, since it is all inviolable; for equal to itself from all directions, it meets uniformly with its limits. At this point, I end for you my reliable account and thought about truth. From here on, learn mortal opinions, listening to the deceitful order of my words. For they established two forms to name in their judgments,24 of which it is not right to name one—in this they have gone astray— and they distinguished things opposite in body, and established signs apart from one another—for one, the aetherial fire of flame, mild, very light, the same as itself in every direction, but not the same as the other; but that other one, in itself is opposite—dark night, a dense and heavy body. I declare to you all the ordering as it appears, 60 so that no mortal judgment may ever overtake you. (Simplicius, Commentary on Aristotle’s Physics 145.1–146.25 [lines 1–52]; 39.1–9 [lines 50–61).

9. (B9) But since all things have been named light and night and the things which accord with their powers have been assigned to these things and those, all is full of light and obscure night together, of both equally, since neither has any share of nothing. (Simplicius, Commentary on Aristotle’s Physics 180.9–12)

10. (B10) You shall know the nature of the Aithēr and all the signs in the Aithēr and the destructive deeds of the shining sun’s pure torch and whence they came to be, {30} and you shall learn the wandering deeds of the round-faced moon and its nature, and you shall know also the surrounding heaven, 5 from what it grew and how Necessity led and shackled it to hold the limits of the stars. (Clement, Miscellanies 5.14; 138.1)

11. (B11) . . . how earth and sun and moon and the Aithēr that is common to all and the Milky Way and furthest Olympus and the hot force of the stars surged forth to come to be. (Simplicius, Commentary on Aristotle’s On the Heavens 559.22–25)

12. (B12) For the narrower <wreaths> were filled with unmixed fire, the ones next to them with night, but a due amount of fire is inserted among it, and in the middle of these is the goddess who governs all things. For she rules over hateful birth and union of all things, sending the female to unite with male and in opposite fashion, 5 male to female. (Simplicius, Commentary on Aristotle’s Physics 39.14–16 [lines 1–3], 31.13–17 [lines 2–6])

13. (B13) First of all gods she contrived Love. (Simplicius, Commentary on Aristotle’s Physics 39.18)

14. (B14) Night-shining foreign light wandering around earth. (Plutarch, Against Colotes 1116A)

15. (B15) Always looking toward the rays of the sun. (Plutarch, On the Face in the Moon 929A)

16. (B16) As on each occasion there is a mixture of the much- wandering limbs, so is mind present to humans; for the same thing is what the nature of the limbs thinks in men, both in all and in each; for the more is thought. (Theophrastus, On the Senses 3;)

17. (B17) [That the male is conceived in the right part of the uterus has been said by others of the ancients. For Parmenides says:] <The goddess brought> boys <into being> on the right <side of the uterus>, girls on the left. (Galen, Commentary on Book VI of Hippocrates’ Epidemics II 46)

18. (B18) As soon as woman and man mingle the seeds of love <that come from> their veins, a formative power fashions well- constructed bodies from their two differing bloods, if it maintains a balance. For if when the seed is mingled the powers clash and do not create a single <power> in the body resulting from the mixture, with double seed they will dreadfully disturb the nascent sex <of the child>. (Caelius Aurelianus, On Chronic Diseases VI.9)

19. (B19) In this way, according to opinion (doxa), these things have grown and now are and afterwards after growing up will come to an end. And upon them humans have established a name to mark each one. (Simplicius, Commentary on Aristotle’s On the Heavens 558.9–11)