Plato

The myth of the cave describes individuals chained deep within the recesses of a cave. Bound so that vision is restricted, they cannot see one another. The only thing visible is the wall of the cave upon which appear shadows cast by models or statues of animals and objects that are passed before a brightly burning fire.

Breaking free, one of the individuals escapes from the cave into the light of day.

With the aid of the sun, that person sees for the first time the real world and returns to the cave with the message that the only things they have seen heretofore are shadows and appearances and that the real world awaits them if they are willing to struggle free of their bonds.

The shadowy environment of the cave symbolizes for Plato the physical world of appearances. Escape into the sun-filled setting outside the cave symbolizes the transition to the real world, the world of full and perfect being, the world of Forms, which is the proper object of knowledge.

The theory of Forms may best be understood in terms of mathematical entities. A circle, for instance, is defined as a plane figure composed of a series of points, all of which are equidistant from a given point. No one has ever actually seen such a figure, however.

What people have actually seen are drawn figures that are more or less close approximations of the ideal circle. In fact, when mathematicians define a circle, the points referred to are not spatial points at all; they are logical points. They do not occupy space.

Nevertheless, although the Form of a circle has never been seen-indeed, could never be seen-mathematicians and others do in fact know what a circle is. That they can define a circle is evidence that they know what it is.

For Plato, therefore, the Form "circularity" exists, but not in the physical world of space and time.

It exists as a changeless object in the world of Forms or Ideas, which can be known only by reason.

Forms have greater reality than objects in the physical world both because of their perfection and stability and because they are models, resemblance to which gives ordinary physical objects whatever reality they have.

Circularity, squareness, and triangularity are excellent examples, then, of what Plato meant by Forms. An object existing in the physical world may be called a circle or a square or a triangle only to the extent that it resembles - "participates in" is Plato's phrase - the Form "circularity" or "squareness" or "triangularity."

Plato extended his theory beyond the realm of mathematics. Indeed, he was most interested in its application in the field of social ethics. The theory was his way of explaining how the same universal term can refer to so many particular things or events.

The word justice, for example, can be applied to hundreds of particular acts because these acts have something in common, namely, their resemblance to, or participation in, the Form "justice."

An individual is human to the extent that he or she resembles or participates in the Form "humanness." If "humanness" is defined in terms of being a rational animal, then an individual is human to the extent that he or she is rational.

A particular act is courageous or cowardly to the extent that it participates in its Form.

An object is beautiful to the extent that it participates in the Idea, or Form, of beauty.

Everything in the world of space and time is what it is by virtue of its resemblance to, or participation in, its universal Form. The ability to define the universal term is evidence that one has grasped the Form to which that universal refers.

Plato conceived the Forms as arranged hierarchically; the supreme Form is the Form of the Good, which, like the sun in the myth of the cave, illuminates all the other Ideas.

There is a sense in which the Form of the Good represents Plato's movement in the direction of an ultimate principle of explanation. The Good is perfect and desired by all who know it. In the Philebus he wonders, Is it pleasure or knowledge?

He shows that pleasure cannot be the Good; pleasures are often accompanied by false opinions, and great pleasures and pains occur in bad states of body or soul.

Knowledge is not perfect either, because some arts are more exact than others.

The Good can be neither knowledge nor pleasure alone, but a mixture of the best parts of both, which include the sciences and those pleasures that are pure and necessary. The best parts of this mixture are beauty, symmetry, and truth, which are all closer to knowledge than pleasure.

He finally gives the order of value as measure, beauty, mind, science, and pure pleasure.

Plato had an essentially antagonistic view of art and the artist, although he approved of certain religious and moralistic kinds of art.