appeals to a standard when she says that a painted portrait of someone is a man. Of course, the pigment on the canvas is not a man; rather, it is properly called a man because it bears a certain relationship to a very different sort of object. In precisely this way, Plato claims that the Forms are what many of our words refer to, even though they are radically different sorts of objects from the ones revealed to the senses.
Love. For Plato the Forms are not merely an unusual item to be added to our list of existing objects. Rather, they are a source of moral and religious inspiration, and their discovery is therefore a decisive turning point in one’s life. This process is described by a fictional priestess named Diotima in the Symposium, a dialogue containing a series of speeches in praise of love and concluding with a remarkable description of the passionate response Socrates inspired in Alcibiades, his most notorious admirer. According to Diotima’s account, those who are in love are searching for something they do not yet understand; whether they realize it or not, they seek the eternal possession of the good, and they can obtain it only through productive activity of some sort. Physical love perpetuates the species and achieves a lower form of immortality, but a more beautiful kind of offspring is produced by those who govern cities and shape the moral characteristics of future generations. Best of all is the kind of love that eventually attaches itself to the Form of Beauty, since this is the most beautiful of all objects and provides the greatest happiness to the lover. One develops a love for this Form by ascending through various stages of emotional attachment and understanding. Beginning with an attraction to the beauty of one person’s body, one gradually develops an appreciation for the beauty present in all other beautiful bodies; then one’s recognition of the beauty in people’s souls takes on increasing strength, and leads to a deeper attachment to the beauty of customs, laws, and systems of knowledge; and this process of emotional growth and deepening insight eventually culminates in the discovery of the eternal and changeless beauty of Beauty itself.
Plato’s theory of erotic passion does not endorse ‘Platonic love,’ if that phrase designates a purely spiritual relationship completely devoid of physical attraction or expression. What he insists on is that desires for physical contact be restrained so that they do not subvert the greater good that can be accomplished in human relationships. His sexual orientation (like that of many of his Athenian contemporaries) is clearly homosexual, and he values the moral growth that can occur when one man is physically attracted to another, but in Book I of the Laws he condemns genital activity when it is homosexual, on the ground that such activity should serve a purely procreative purpose.
Plato’s thoughts about love are further developed in the Phaedrus. The lover’s longing for and physical attraction to another make him disregard the norms of commonplace and dispassionate human relationships: love of the right sort is therefore one of four kinds of divine madness. This fourfold classificatory scheme is then used as a model of proper methodology. Starting with the Phaedrus, classification – what Plato calls the ‘collection and division of kinds’ – becomes the principal method to be used by philosophers, and this approach is most fully employed in such late works as the Sophist, Statesman, and Philebus. Presumably it contributed to Aristotle’s interest in categories and biological classification. The Republic. The moral and metaphysical theory centered on the Forms is most fully developed in the Republic, a dialogue that tries to determine whether it is in one’s own best interests to be a just person. It is commonly assumed that injustice pays if one can get away with it, and that just behavior merely serves the interests of others. Plato attempts to show that on the contrary justice, properly understood, is so great a good that it is worth any sacrifice. To support this astonishing thesis, he portrays an ideal political community: there we will see justice writ large, and so we will be better able to find justice in the individual soul. An ideal city, he argues, must make radical innovations. It should be ruled by specially trained philosophers, since their understanding of the Form of the Good will give them greater insight into everyday affairs. Their education is compared to that of a prisoner who, having once gazed upon nothing but shadows in the artificial light of a cave, is released from bondage, leaves the cave, eventually learns to see the sun, and is thereby equipped to return to the cave and see the images there for what they are. Everything in the rulers’ lives is designed to promote their allegiance to the community: they are forbidden private possessions, their sexual lives are regulated by eugenic considerations, and they are not to know who their children are. Positions of political power are open to women, since the physical differences between them and men do not in all cases deprive them of the intellectual or moral capacities needed for political office. The works of poets are to be carefully regulated, for the false moral notions of the traditional poets have had a powerful and deleterious impact on the general public. Philosophical reflection is to replace popular poetry as the force that guides moral education. What makes this city ideally just, according to Plato, is the dedication of each of its components to one task for which it is naturally suited and specially trained. The rulers are ideally equipped to rule; the soldiers are best able to enforce their commands; and the economic class, composed of farmers, craftsmen, builders, and so on, are content to do their work and to leave the tasks of making and enforcing the laws to others. Accordingly what makes the soul of a human being just is the same principle: each of its components must properly perform its own task. The part of us that is capable of understanding and reasoning is the part that must rule; the assertive part that makes us capable of anger and competitive spirit must give our understanding the force it needs; and our appetites for food and sex must be trained so that they seek only those objects that reason approves. It is not enough to educate someone’s reason, for unless the emotions and appetites are properly trained they will overpower it. Just individuals are those who have fully integrated these elements of the soul. They do not unthinkingly follow a list of rules; rather, their just treatment of others flows from their own balanced psychological condition. And the paradigm of a just person is a philosopher, for reason rules when it becomes passionately attached to the most intelligible objects there are: the Forms. It emerges that justice pays because attachment to these supremely valuable objects is part of what true justice of the soul is. The worth of our lives depends on the worth of the objects to which we devote ourselves. Those who think that injustice pays assume that wealth, domination, or the pleasures of physical appetite are supremely valuable; their mistake lies in their limited conception of what sorts of objects are worth loving.
Late dialogues. The Republic does not contain Plato’s last thoughts on moral or metaphysical matters. For example, although he continues to hold in his final work, the Laws, that the family and private wealth should ideally be abolished, he describes in great detail a second-best community that retains these and many other institutions of ordinary political life. The sovereignty of law in such a state is stressed continually; political offices are to be filled by elections and lots, and magistrates are subject to careful scrutiny and prosecution. Power is divided among several councils and offices, and philosophical training is not a prerequisite for political participation. This second-best state is still worlds apart from a modern liberal democracy – poetic works and many features of private life are carefully regulated, and atheism is punished with death – but it is remarkable that Plato, after having made no concessions to popular participation in the Republic, devoted so much energy to finding a proper place for it in his final work. Plato’s thoughts about metaphysics also continued to evolve, and perhaps the most serious problem in interpreting his work as a whole is the problem of grasping the direction of these further developments. One notorious obstacle to understanding his later metaphysics is presented by the Parmenides, for here we find an unanswered series of criticisms of the theory of Forms. For example, it is said that if there is reason to posit one Form of Largeness (to select an arbitrary example) then there is an equally good reason to posit an unlimited number of Forms of this type. The ‘first’ Form of Largeness must exist because according to Plato whenever a number of things are large, there is a Form of Largeness that makes them large; but now, the argument continues, if we consider this Form together with the other large things, we should recognize still another Form, which makes the large things and Largeness itself large. The argument can be pursued indefinitely, but it seems absurd that there should be an unlimited number of Forms of this one type. (In antiquity the argument was named the Third Man, because it claims that in addition to a second type of object called ‘man’ – the Form of Man – there is even