Three Platonic Theories

The Theory of Forms

The Death of Socrates, by Jacques-Louis David, 1787. The Death of Socrates

Plato is seated at the end of the bed. Socrates reaches for the hemlock. His friends are weeping. In the Phaedo, the character tells Crito not to forget that "we owe a cock to Asclepius" (118a8-9). Crito replies that "[i]t shall be done." He asks Socrates whether he has "anything else to say" (9-10), but Socrates does not reply. He has died, and Phaedo brings his account to a close: "[s]uch was the end of our comrade, a man who, we would say, was of all those we have known, the best, and also the wisest and most upright" (a15-17).
The Phaedo shows Socrates on the day of his execution. The dialogue is devoted to showing that the lover of wisdom should not fear death. His primary interlocutors are Pythagoreans. Socrates argues that death is the separation of the soul from the body and that the body stands in the way of wisdom. In death, the soul has the knowledge of forms the lover of wisdom seeks. Elea was a Greek city in what is now southern Italy.

In this way, in the Phaedo, there is an explanation of what the good life is. The wisdom the love of wisdom seeks transforms the human psychology so that a human being engages in a certain intellectual activity as much as possible. This intellectual activity imitates the existence the soul enjoys in its natural and disincarnate state, a state in which is somehow completely characterized by knowledge of things Socrates calls "forms" (εἴδη) and that somehow are the reality of things. The good life for a human being is an existence that, as much as possible, resembles the natural and disincarnate existence in which the soul is fixed in "contemplation" (θεωρία).

Orphism and Pythagoreanism

This otherworldly outlook seems to have connections to Orphism and Pythagoreanism.

In the Orphic religious movement (which takes its name form the mythical musician and poet Orpheus), there is the idea that the afterlife need not be gloomy and that the soul can be purified. This idea, which is contrary to the picture of the afterlife in Homer, is also part of Pythagoreanism.


Simmias and Cebes are students of the Philolaus (Phaedo 61d). Philolaus was a Pythagorean from Croton (in what is now the south of Italy) and a contemporary of Socrates. Pythagoras founded his school in Croton in about 530 BCE.

Orpheus was said to born of the Muse, Calliope. To be "musical" is to be skilled an art over which the Muses presided. The word is used generally of a person of letters and accomplishments. The opposite is to be ἀμαθής. To be ἀμαθής is to be "unlearned, ignorant, stupid, or boorish."
In the Apology, Socrates says he is willing to die many times over if it meant he would meet Orpheus in the afterlife (41a). In the Phaedo, on the day of his death, his final conversation is with Simmias and Cebes. Socrates tries to show them that the "lover of wisdom" (φιλόσοφος) should not fear death and that those who pursue the "love of wisdom" (φιλοσοφία) correctly are practicing for their existence when they are dead (61c-d, 63b-c, 63e-64a). Socrates has said previously, at Phaedo 60e-61a, that he has had a dream in which he was instructed to cultivate the Muses and that he thought the instruction was to do what he had been doing because the "love of wisdom" (φιλοσοφία) is the greatest kind of "music" (μουσικῆς). In the Crito, at 45b, Simmias and Cebes are said to have brought money to aid Socrates in escaping from jail.

In the Meno, at 81a-b, in connection with the Theory of Recollection, Socrates seems to have the Orphics or the Pythagoreans in mind. He tells Meno, in his introduction to the theory, that he has heard from "certain priests and priestesses" that "the soul of man is immortal, and at one time comes to an end, which is called dying, and at another is born again, but never perishes."

Socrates Turns to the Forms

"When I was young, Cebes, I was tremendously eager for the kind of wisdom (σοφίας) they call inquiry about nature (περὶ φύσεως ἱστορίαν)" (Phaedo 96a).

Other than the remark in the Phaedo, there is little evidence to show that Socrates was ever "eager" for the inquiry into nature. Diogenes Laertius says that Archelaus (a student of Anaxagoras) brought natural philosophy (φυσικὴν φιλοσοφίαν) to Athens and that Socrates was his student (Lives of the Philosophers II.16), and it is possible that Archelaus is the author of some of the views Aristophanes associates with Socrates in the Clouds. Plato, however, in the Apology, has Socrates deny that he ever pursued the inquiry into nature. "For many accusers have risen up against me before you, who have been speaking for a long time, many years already, and saying nothing true.... [T]hey got hold of most of you in childhood, and accused me without any truth, saying, 'There is a certain Socrates, a wise man, a ponderer over the things in the air and one who has investigated the things beneath the earth and who makes the weaker argument the stronger'" (Apology 18b; cf. Apology 19b-d, 23c-d, 26d).)
In the course of arguing that the soul survives death, Socrates sets out his intellectual autobiography as a prelude to a general discussion of the cause of generation and destruction. He says, in this autobiography, that he was interested in the inquiry into nature when he was young.

This interest in the inquiry into nature is surprising. The early dialogues give no hint that Socrates was ever interested in the inquiry into nature. In fact, it is easy to get the impression that he thought that such knowledge might be impossible and that even if it were possible, it would not be part of the wisdom he wants. Socrates interest in the early dialogues is in ethical matters.

Why, then, does Plato represent Socrates as having been interested in the the inquiry into nature? The answer, it seems, is that Plato wants to show that Socrates' interest in definitions points the way to the "otherwordly" interpretation of the good life in the middle dialogues.

Plato seems to think that the inquirers into nature tried to get straight on the reality of things but made a mistake of the kind to which Socrates calls attention in the early dialogues. Socrates, in these dialogues, is looking for the universal in some ethical matter, not for the way this universal manifests itself in particular circumstances. He tells Euthyphro, for example, not to reply to the "What is piety?" question by citing "one or two out of all the numerous actions that are pious," but to tell him "about the form itself by which all pious things are pious" (Euthyphro 6d).

"If anyone says to me that a given thing is beautiful because it has a blooming color, or a shape, or something else like that, I dismiss those other things, for all those things confuse me, and I hold simply and plainly and perhaps foolishly to this, that nothing else makes it beautiful but the presence or communion (call it which you please) of the beautiful itself (αὐτὸ καλὸν), however it may have been gained; about the way in which it happens, I make no positive statement as yet, but I do insist that beautiful things are made beautiful by the beautiful" (Phaedo 100c). The answers Socrates considered when in his youth he was interested in the inquiry into nature are like the ones he admonishes Euthyphro for giving. Socrates says that when he pursued this inquiry in his youth he went back and forth with respect to the following kinds of questions. "Do heat and cold, by a sort of fermentation, bring about the organization of animals, as some people say? Is the blood, or air, or fire by which we think? Or is it none of these, and does the brain furnish the sensations of hearing and sight and smell, and do memory and opinion arise from these, and does knowledge come from memory and opinion in a state of rest" (Phaedo 96b)?

This is why Socrates (as Plato portrays him) abandoned the inquiry into nature for his interest in forms. He realized that the inquirers into nature were giving the wrong kind of answers to their questions. What thinking is, for example, is not "blood" or any such thing like that. Answers of this kind make the mistake Socrates' interlocutors make in the early dialogues. It may be that thinking involves "blood" or "air" in some circumstances, but none of these things is what thinking is.

The Life of "Contemplation"

"[P]hilosophy (φιλοσοφία) sees that the most dreadful thing about the imprisonment in the body is the fact that it is caused by the lusts (ἐπιθυμίας) of the flesh, so that the prisoner is the chief assistant in his own imprisonment. ... The soul of the true philosopher (ἀληθῶς φιλοσόφου ψυχὴ) ... stands aloof from pleasures and lusts and griefs and fears (ἡδονῶν τε καὶ ἐπιθυμιῶν καὶ λυπῶν καὶ φόβων), so far as it can, considering that when anyone has violent pleasures or fears or griefs or lusts he suffers from them not merely what one might think--for example, illness or loss of money spent or his lusts--but he suffers the greatest and most extreme evil and does not take it into account. ... The evil is that the soul of every man, when it is greatly pleased or pained by anything, is compelled to believe that the object which caused the emotion (πάσχῃ) is very distinct and very true; but it is not. ... Each pleasure or pain bonds the soul as with a nail to the body and rivets it on and makes it corporeal, so that it fancies the things are true which the body says are true. For because it has the same beliefs and pleasures as the body it is compelled to adopt also the same habits and mode of life (ἐκ γὰρ τοῦ ὁμοδοξεῖν τῷ σώματι καὶ τοῖς αὐτοῖς χαίρειν ἀναγκάζεται οἶμαι ὁμότροπός τε καὶ ὁμότροφος γίγνεσθαι), and can never depart in purity to the other world, but must always go away contaminated with the body; and so it sinks quickly into another body again and grows into it, like seed that is sown. Therefore it has no part in the communion with the divine and pure and absolute. ... This, Cebes, is the reason why the true lovers of knowledge (φιλομαθεῖς) are temperate (κόσμιοί) and brave (ἀνδρεῖοι).... For the soul of the philosopher would not reason (λογίσαιτ᾽) as others do, and would not think it right that philosophy should set it free and that then when set free it should give itself again into bondage to pleasure and pain and engage in futile toil.... No, his soul believes that it must gain peace from these emotions, must follow reason (λογισμῷ) and abide always in it, beholding that which is true and divine and not a matter of opinion (τὸ ἀληθὲς καὶ τὸ θεῖον καὶ τὸ ἀδόξαστον), and making that its only food; and in this way it believes it must live, while life endures, and then at death pass on to that which is akin to itself and of like nature, and be free from human ills" (Phaedo 82e-84b). Now the reasons for the otherworldly perspective in the middle dialogues are a little clearer. Plato understands Socrates' search for definitions as an interest in the forms of things, where these forms are the reality and existence of the things he Socrates is asking about. In its natural and disincarnate state, the soul is somehow fixed in "contemplation" (θεωρία) of forms. When the soul enters the body, it forgets itself and its good and wrongly takes on the concerns of the body. Socrates, as Plato seems to understand him, lived in a way that corrects this mistake. In neglecting the things ordinarily thought to be good, and instead spending his life in the love of wisdom in the search for definitions, his existence is like the one he expects to have outside the body.

It is also a little clearer how Plato understands the suggestion in the early dialogues that the person who is just and has the rest of the traditional virtues is the one who chooses wisely and thus arranges things in his life so that he is "happy" (εὐδαίμων). The person who acts in terms of these virtues is the person who arranges things in his life so that lives in contemplation of the forms. Socrates gives this explanation in the passage that is sometimes called his "second" defense.

"My dear Simmias, I suspect that this is not the right way to purchase virtue (ἀρετὴν), by exchanging pleasures for pleasures, and pains for pains, and fear for fear, and greater for less, as if they were coins, but the only right coinage, for which all those things must be exchanged and by means of and with which all these things are to be bought and sold, is in fact wisdom; and courage and temperance and justice and, in short, true virtue exist only with wisdom, whether pleasures and fears and other things of that sort are added or taken away. And virtue which consists in the exchange of such things for each other without wisdom, is but a painted imitation of virtue and is really slavish and has nothing healthy or true in it; but whereas, truth to tell, temperance and justice and courage may in fact be a kind of purification of all such things, and wisdom itself a kind of purification (καθαρμός τις). And I fancy that those men who established the mysteries were not unenlightened, but in reality had a hidden meaning when they said long ago that whoever goes uninitiated and unsanctified to the other world will lie in the mire, but he who arrives there initiated and purified will dwell with the gods. For as they say in the mysteries, 'the thyrsus-bearers are many, but the mystics few'; and these mystics are, I believe, those who have practiced philosophy correctly (οἱ πεφιλοσοφηκότες ὀρθῶς). And I in my life have, so far as I could, left nothing undone, and have striven in every way to make myself one of them. But whether I have striven aright and have met with success, I believe I shall know clearly, when I have arrived there, very soon, God willing. There is my defense, then, Simmias and Cebes, to show that it is reasonable for me not to be grieved or troubled at leaving you..." (Phaedo 69a-69d).

Forms are Paradigms Fixed in Nature

The dramatic date of the Parmenides is 450 BCE (Parmenides 127b). This is Plato's earliest depiction of Socrates.

The Parmenides is traditionally thought to be a late dialogue.
In the Parmenides, Socrates says that "I think the most likely view is this: that the forms exist as paradigms set in nature, and other things resemble them and are imitations and this partaking of forms is, for the other things, simply being modeled after them" (Parmenides 132d).

This suggests, given that forms are the "paradigms" specified in reply to the request for a definition (the "what is it?" question), that what Socrates is asking about is "a paradigm set in nature."

"The philosophies described above were succeeded by the system of Plato, which in most respects accorded with them, but contained also certain peculiar features distinct from the philosophy of the Italians. In his youth Plato first became acquainted with Cratylus and the Heraclitean doctrines--that the whole sensible world is always in a state of flux (ἀεὶ ῥεόντων), and that there is no knowledge of it--and in after years he still held these opinions. And when Socrates, disregarding the physical universe (τῆς ὅλης φύσεως) and confining his study to ethical questions, sought in this sphere for the universal (καθόλου) and was the first to concentrate upon definition. Plato followed him and assumed that the problem of definition is concerned not with any sensible thing but with entities of another kind; for the reason that there can be no general definition of sensible things, as they are always changing (ἀεί γε μεταβαλλόντων). These entities he called Ideas (ἰδέας), and held that all sensible things are named after them and in virtue of their relation to them; for the plurality of things which bear the same name as the forms exist by participation in them" (Metaphysics I.6.987a-b).

"The theory of forms (εἰδῶν) occurred to those who enunciated it because they were convinced as to the true nature of reality by the doctrine of Heraclitus, that all sensible things are always in a state of flux (ἀεὶ ῥεόντων); so that if there is to be any knowledge..., there must be certain other entities, besides sensible ones, which persist. For there can be no knowledge of that which is in flux. Now Socrates devoted his attention to the virtues of character, and was the first to seek a general definition of these. ... and he naturally inquired into the essence of things (τὸ τί ἐστιν); for he was trying to reason logically, and the starting-point of all logical reasoning is the essence. ... But whereas Socrates regarded neither universals nor definitions as existing in separation (χωριστὰ), they gave them a separate existence, and to these universals and definitions of existing things they gave the name of Ideas (ἰδέας)" (Metaphysics XIII.4.1078b).
It is not clear why Plato finds this way of thinking about forms plausible, but he seems to think first of all that the things Socrates asks about are objective. In the Euthyphro, he asks Euthyphro to tell him what piety is. This seems to presuppose there is something piety is. This is the "form" (εἶδος) of pious things and that according to which any given thing either is or is not pious.

Further, according to Aristotle, who entered Plato's Academy as a teenager and remained there until Plato's death some twenty years later, Plato thinks that the forms do not exist among the sensible things. Aristotle reports that Plato thought that whereas the forms are unchanging, there is nothing like that among the sensible things. Plato, according to Aristotle, thought that the sensible things exist in a way that they are somehow in "flux" and are "always changing."

This is consistent with the Phaedo. Plato, it seems, thinks that the forms are the "reality" (οὐσία) of sensible things and that the existence of the reality of sensible things is different from the existence of the sensible things. The sensible things are always changing. The forms are not.

Let us then, Cebes, turn to what we were discussing before. Is the being itself (αὐτὴ ἡ οὐσία), which we in our dialectic process of question and answer call true being, always the same or is it liable to change? Does the equal itself, the beautiful itself, what each thing is itself, that which is, ever admit of any change whatsoever? Or does what each of them is, being uniform and existing by itself, remain the same and never in any way admit of any change?
It must necessarily remain the same, Socrates.
But how about the many things, for example, men, or horses, or cloaks, or any other such things, which bear the same names as those objects and are called beautiful or equal or the like? Are they always the same? Or are they, in direct opposition to those others, constantly changing in themselves, unlike each other, and, so to speak, never the same?
The latter, they are never the same.
And you can see these and touch them and perceive them by the other senses, whereas the things which are always the same can be grasped only by the reason, and are invisible and not to be seen?” Certainly that is true.
In his Metaphysics, Aristotle returns to the question of the reality of things that Plato introduces in the Phaedo. Now, shall we assume two kinds of existences, one visible, the other invisible?
Let us assume them" (Phaedo 78c-79a).






Perseus Digital Library:

Plato, Phaedo, Parmenides.
Aristotle, Metaphysics

Henry George Liddell, Robert Scott, A Greek-English Lexicon:
εἶδος, eidos, noun, "form, shape,"
θεωρία, theōria, noun, "viewing, beholding,"
μουσική, mousikē, noun, "art over which the Muses presided,"
παράδειγμα, paradeigma, noun, "pattern, model,"
ῥέω, rheō, verb, "to flow, run, stream, gush"

Arizona State University Library. Loeb Classical Library:
Early Greek Philosophy, Volume IV: Western Greek Thinkers, Part 1,
Early Greek Philosophy, Volume IV: Western Greek Thinkers, Part 2



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