_c._ In the Philebus Plato investigates the nature of pleasure; and the opposition of the infinite and finite, or of the unlimited (ἄπειρον) and limiting (πέρας), is there more especially dealt with. In keeping this before us, it would scarcely occur to us that through the metaphysical knowledge of the nature of the infinite and undetermined, what concerns enjoyment is likewise determined; but these pure thoughts are the substantial through which everything, however concrete or seemingly remote, is decided. When Plato treats of pleasure and wisdom as contrasted, it is the opposition of finite and infinite. By pleasure we certainly represent to ourselves the immediately individual, the sensuous; but pleasure is the indeterminate in respect that it is the merely elementary, like fire and water, and not the self-determining. Only the Idea is the self-determinate, or self-identity. To our reflection the infinite appears to be what is best and highest, limitation being inferior to it; and ancient philosophers so determined it. By Plato, however, it is, on the other hand, shown that the limited is the true, as the self-determining, while the unlimited is still abstract; it certainly can be determined in many different ways, but when thus determined it is only the individual. The infinite is the formless; free form as activity is the finite, which finds in the infinite the material for self-realization. Plato thus characterizes enjoyment dependent on the senses as the unlimited which does not determine itself; reason alone is the active determination. But the infinite is what in itself passes over to the finite; thus the perfect good, according to Plato, is neither to be sought for in happiness or reason, but in a life of both combined. But wisdom, as limit, is the true cause from which what is excellent arises.[42] As that which posits measure and end, it is what absolutely determines the end—the immanent determination with which and in which freedom likewise brings itself into existence.