Before closing our discussion of dialectic, it may be well to consider what place it occupies in the life of man, and what importance is attached to it. Here Plato's answer is emphatic. Dialectic is the crown of knowledge, and knowledge is the crown of life. All other spiritual activities have value only in so far as they lead up to the knowledge of the Idea. All other subjects of intellectual study are merely preparatory to the study of philosophy. The special sciences have no value in themselves, but they have value inasmuch as their definitions and classifications form a preparation for the knowledge of Ideas. Mathematics is important because it is a stepping-stone from the world of sense to the Ideas. Its objects, namely, numbers and geometrical figures, resemble the Ideas in so far as they are immutable, and they resemble sense-objects in so far as they are in space or time. In the educational curriculum of Plato, philosophy comes last. Not everyone may study it. And none may study it till he has been through all the preparatory stages of education, which form a rigorous discipline of the mind before it finally enters upon dialectic. Thus all knowledge ends in dialectic, and that life has not attained its end which falls short of philosophy. Perhaps the most striking illustration of the subordination of all spiritual activities to philosophy is to be found in the doctrine of Eros, or Love. The phrase "platonic love" is on the lips of many, but, as a rule, something very different from Plato's own doctrine is meant. According to him, love is always concerned with beauty, and his teaching on the subject is expounded {205} chiefly in the "Symposium," He believed that before birth the soul dwelt disembodied in the pure contemplation of the world of Ideas. Sinking down into a body, becoming immersed in the world of sense, it forgets the Ideas. The sight of a beautiful object reminds it of that one Idea of beauty of which the object is a copy. This accounts for the mystic rapture, the emotion, the joy, with which we greet the sight of the beautiful. Since Plato had expressly declared that there are Ideas of the ugly as well as of the beautiful, that there are Ideas, for example, of hair, filth, and dirt, and since these Ideas are just as divine and perfect as the Idea of the beautiful, we ought, on this theory, to greet the ugly, the filthy, and the nauseating, with a ravishment of joy similar to that which we experience in the presence of beauty. Why this is not the case Plato omitted to explain. However, having learned to love the one beautiful object, the soul passes on to the love of others. Then it perceives that it is the same beauty which reveals itself in all these. It passes from the love of beautiful forms to the love of beautiful souls, and from that to the love of beautiful sciences. It ceases to be attached to the many objects, as such, that is to say, to the sensuous envelopes of the Idea of beauty. Love passes into the