PLATO

Plato was the most famous student of Socrates (c. 470– 399 BCE), the teacher of Aristotle (384–322 BCE), and the founder of the Academy. He is best known as the author of philosophical works of unparalleled influence. The son of Ariston (his father) and Perictione (his mother), Plato was born in the year after the death of the great Athenian statesman Pericles. His brothers Glaucon and Adeimantus are portrayed as interlocutors in Plato’s masterpiece the Republic, and his half brother Antiphon figures in the Parmenides. 

Plato’s family was aristocratic and distinguished: his father’s side claimed descent from the god Poseidon, and his mother’s side was related to the lawgiver Solon (c. 630–560 BCE). Less creditably, his mother’s close relatives Critias and Charmides were among the Thirty Tyrants who seized power in Athens and ruled briefly until the restoration of democracy in 403.Plato as a young man was a member of the circle around Socrates. Since the latter wrote nothing, what is known of his characteristic activity of engaging his fellow citizens (and the occasional itinerant celebrity) in conversation derives wholly from the writings of others, most notably Plato himself. 

The works of Plato commonly referred to as “Socratic” represent the sort of thing the historical Socrates was doing.Plato was profoundly affected by both the life and the death of Socrates. The activity of the older man provided the starting point of Plato’s philosophizing. In fact, his classic Apology purports to be the speech Socrates gave at his trial in response to the accusations made against him (Greek apologia means “defense”). Its powerful advocacy of the examined life and its condemnation of Athenian democracy have made it one of the central documents of Western thought and culture.

Plato’s motives in writing the Apology are likely to have been complex. One of them, no doubt, was to defend and praise Socrates by making use of many of the points Socrates himself had offered in his speech. But Plato is at the same time using the trial and death of Socrates to condemn Athens, to call upon his readers to reject the conventional life that Athens would have preferred Socrates to lead, and to choose instead the life of a Socratic philosopher. In the 4th century BCE Athens had no norm of accurate reportage or faithful biography, and so Plato would have felt free to shape his material in whatever way suited his mulitple aims. Because it was Socrates he wished to praise, he had no choice but to make the Socrates of the Apology close to the original. But he would not have felt bound merely to reproduce, as best he could, the speech that Socrates delivered.

Plato’s Academy, founded in the 380s, was the ultimate ancestor of the modern university (hence the English term academic); an influential centre of research and learning, it attracted many men of outstanding ability. For 20 years Aristotle was also a member of the Academy. He started his own school, the Lyceum, only after Plato’s death, when he was passed over as Plato’s successor at the Academy, probably because of his connections to the court of Macedonia.

HAPPINESS AND VIRTUE

The characteristic question of ancient ethics is “How can I be happy?” and the basic answer is “by means of virtue.” But in the relevant sense of the word, happiness— the conventional English translation of the ancient Greek eudaimonia—is not a matter of mood or emotional state. Rather, as in a slightly archaic English usage, it is a matter of having things go well. Being happy in this sense is living a life of what some scholars call “human flourishing.” Thus, the question “How can I be happy?” is equivalent to “How can I live a good life?”

Whereas the notion of happiness in Greek philosophy applies at most to living things, that of arete—“virtue” or “excellence”—applies much more widely. Anything that has a characteristic use, function, or activity has a virtue or excellence, which is whatever disposition enables things of that kind to perform well. The excellence of a race horse is whatever enables it to run well; the excellence of a knife is whatever enables it to cut well; and the excellence of an eye is whatever enables it to see well. Human virtue, accordingly, is whatever enables human beings to live good lives. 

Thus the notions of happiness and virtue are linked.But it is far from obvious what a good life consists of, and so it is difficult to say what virtue, the condition that makes it possible, might be. Already by Plato’s time a conventional set of virtues had come to be recognized by the larger culture; they included courage, justice, piety, modesty or temperance, and wisdom. Socrates and Plato undertook to discover what these virtues really amount to. A truly satisfactory account of any virtue would identify what it is, show how possessing it enables one to live well, and indicate how it is best acquired.In Plato’s representation of the activity of the historical Socrates, the interlocutors are examined in a search for definitions of the virtues. 

It is important to understand, however, that the definition sought for is not lexical, merely specifying what a speaker of the language would understand the term to mean as a matter of linguistic competence. Rather, the definition is one that gives an account of the real nature of the thing named by the term; accordingly, it is sometimes called a “real” definition. The real definition of water, for example, is H2O, though speakers in most historical eras did not know this.

THE REPUBLIC 

In The Republic, a Socratic dialogue that is considered one of the most influential works of philosophical thought, Plato develops a unique view of happiness and virtue. According to Plato, there are three parts of the soul, each with its own object of desire. Reason desires truth and the good of the whole individual, spirit is preoccupied with honor and competitive values, and appetite has the traditional low tastes for food, drink, and sex. Because the soul is complex, erroneous calculation is not the only way it can go wrong. 

The three parts can pull in different directions, and the low element, in a soul in which it is overdeveloped, can win out. Correspondingly, the good condition of the soul involves more than just cognitive excellence. In the terms of The Republic, the healthy or just soul has psychic harmony—the condition in which each of the three parts does its job properly.Although the dialogue starts from the question “Why should I be just?,” Socrates proposes that this inquiry can be advanced by examining justice “writ large” in an ideal city. Thus, the political discussion is undertaken to aid the ethical one. One early hint of the existence of the three parts of the soul in the individual is the existence of three classes in the well-functioning state: rulers, guardians, and producers. 

The wise state is the one in which the rulers understand the good; the courageous state is that in which the guardians can retain in the heat of battle the judgments handed down by the rulers about what is to be feared; the temperate state is that in which all citizens agree about who is to rule; and the just state is that in which each of the three classes does its own work properly.Justice as conceived in The Republic is so comprehensive that a person who possessed it would also possess all the other virtues, thereby achieving “the health of that whereby we live [the soul].” 

Yet, lest it be thought that habituation and correct instruction in human affairs alone can lead to this condition, one must keep in view that The Republic also develops the famous doctrine according to which reason cannot properly understand the human good or anything else without grasping the form of the Good itself. Thus the original inquiry, whose starting point was a motivation each individual is presumed to have (to learn how to live well), leads to a highly ambitious educational program. 

Starting with exposure only to salutary stories, poetry, and music from childhood and continuing with supervised habituation to good action and years of training in a series of mathematical disciplines, this program—and so virtue—would be complete only in the person who was able to grasp the first principle, the Good, and to proceed on that basis to secure accounts of the other realities. There are hints in The Republic, as well as in the tradition concerning Plato’s lecture On the Good and in several of the more technical dialogues, that this first principle is identical with Unity, or the One.

THE THEORY OF FORMS 

Plato is both famous and infamous for his theory of forms. Just what the theory is, and whether it was ever viable, are matters of extreme controversy. To readers who approach Plato in English, the relationship between forms and sensible particulars, called in translation “participation,” seems purposely mysterious. Moreover, the claim that the sensible realm is not fully real, and that it contrasts in this respect with the “pure being” of the forms, is perplexing. A satisfactory interpretation of the theory must rely on both historical knowledge and philosophical imagination.

FORMS AS PERFECT EXEMPLARS 

According to a view that some scholars have attributed to Plato’s middle dialogues, participation is imitation or resemblance. Each form is approximated by the sensible particulars that display the property in question. Thus, Achilles and Helen are imperfect imitations of the Beautiful, which itself is maximally beautiful. On this interpretation, the “pure being” of the forms consists of their being perfect exemplars of themselves and not exemplars of anything else. Unlike Helen, the form of the Beautiful cannot be said to be both beautiful and not beautiful— similarly for Justice, Equality, and all the other forms.This “super-exemplification” interpretation of participation provides a natural way of understanding the notion of the pure being of the forms and such self-predication sentences as “the Beautiful is beautiful.” Yet it is absurd. 

In Plato’s theory, forms play the functional role of universals, and most universals, such as greenness, generosity, and largeness, are not exemplars of themselves. (Greenness does not exhibit hue; generosity has no one to whom to give; largeness is not a gigantic object.) Moreover, it is problematic to require forms to exemplify only themselves, because there are properties, such as being and unity, that all things, including all forms, must exhibit. (So Largeness must have a share of Being to be anything at all, and it must have a share of Unity to be a single form.) Plato was not unaware of the severe difficulties inherent in the super-exemplification view; indeed, in the Parmenides and the Sophist he became the first philosopher to demonstrate these problems.

The first part of the Parmenides depicts the failure of the young Socrates to maintain the super-exemplification view of the forms against the critical examination of the older philosopher Parmenides. Since what Socrates there says about forms is reminiscent of the assertions of the character Socrates in the middle dialogues Symposium, Phaedo, and Republic, the exchange is usually interpreted as a negative assessment by Plato of the adequacy of his earlier presentation. Those who consider the first part of the Parmenides in isolation tend to suppose that Plato had heroically come to grips with the unviability of his theory, so that by his late period he was left with only dry and uninspiring exercises, divorced from the exciting program of the great masterpieces. 

Those who consider the dialogue as a whole, however, are encouraged by Parmenides’ praise for the young Socrates and by his assertion that the exercise constituting the second part of the dialogue will help Socrates to get things right in the future. This suggests that Plato believed that the theory of forms could be developed in a way that would make it immune to the objections raised against the super-exemplification view.

FORMS AS GENERA AND SPECIES 

Successful development of the theory of forms depended upon the development of a distinction between two kinds of predication. Plato held that a sentence making a predication about a sensible particular, “A is B,” must be understood as stating that the particular in question, A, displays a certain property, B. There are ordinary predications about the forms, which also state that the forms in question display properties. Crucially, however, there is also a special kind of predication that can be used to express a form’s nature. Since Plato envisaged that these natures could be given in terms of genus-species trees, a special predication about a form, “A is B,” is true if B appears above A in its correct tree as a differentia or genus. 

Equivalently, “A is B” has the force that being a B is (part of) what it is to be an A. This special predication is closely approximated in modern classifications of animals and plants according to a biological taxonomy. “The wolf is a canis,” for example, states that “wolf” appears below “canis” in a genus-species classification of the animals, or equivalently that being a canis is part of what it is to be a wolf (Canis lupus).

Plato’s distinction can be illustrated by examples such as the following. The ordinary predication “Socrates is just” is true, because the individual in question displays the property of being just. Understood as a special predication, however, the assertion is false, because it is false that being just is part of what it is to be Socrates (there is no such thing as what it is to be Socrates). “Man is a vertebrate,” understood as an ordinary predication, is false, since the form Man does not have a backbone. But when treated as a special predication it is true, since part of what it is to be a human is to be a vertebrate. Self-predication sentences are now revealed as trivial but true: “the Beautiful is beautiful” asserts only that being beautiful is (part of) what it is to be beautiful. In general one must be careful not to assume that Plato’s self-predication sentences involve ordinary predication, which would in many cases involve problematic self-exemplification issues.

By means of special predication it is possible to provide an account of each fundamental nature. Such accounts, moreover, provide a way of understanding the “pure being” of the forms: it consists of the fact that there cannot be a true special predication of the form “A is both B and not-B.” In other words, special predication sentences do not exhibit the phenomenon of rolling around between being and not being. This is because it must be the case that either B appears above A in a correct genus-species classification or it does not. Moreover, since forms do not function by being exemplars of themselves only, there is nothing to prevent their having other properties, such as being and unity, as appropriate. As Plato expresses it, all forms must participate in Being and Unity. 

Because the special predications serve to give (in whole or in part) the real definitions that Socrates had been searching for, this interpretation of the forms connects Plato’s most technical dialogues to the literary master-pieces and to the earlier Socratic dialogues. The technical works develop a schema that, with modifications of course, went on to be productive in the work of Aristotle and many later researchers. In this way, Plato’s late theory of the forms grows out of the program of his teacher and leads forward to the research of his students and well beyond.