Plato and Aristotle, though they differ on certain points of detail, are agreed that the influence of music on character, for good or bad, is enormous. Music, they say, is the most imitative of all the arts. The various rhythms, times, and scales imitate different tempers and emotional moods, and it is a fundamental law of our nature that we grow like what we take pleasure in seeing or having imitated or represented for us. Hence if we are early accustomed to take pleasure in the imitation of the manly, resolute, and orderly, these qualities will in time become part of our own nature. This is why right musical education is so important that Plato declared that the revolutionary spirit always makes its first appearance in innovations on established musical form. There is, however, one important difference between the two philosophers which must be noted, because it concerns Aristotle’s chief contribution to the philosophy of fine art. Plato had in the _Republic_ proposed to expel florid, languishing, or unduly exciting forms of music not only from the schoolroom, but from life altogether, on the ground of their unwholesome tendency to foster an unstable and morbid character in those who enjoy them. For the same reason he had proposed the entire suppression of tragic drama. Aristotle has a theory which is directly aimed against this overstrained Puritanism. He holds that the exciting and sensational art which would be very bad as daily food may be very useful as an occasional medicine for the soul. He would retain even the most sensational forms of music on account of what he calls their "purgative" value. In the same spirit he asserts that the function of tragedy, with its sensational representations of the calamities of its heroes, is "by the vehicle of fear and pity to purge our minds of those and similar emotions." The explanation of the theory is to be sought in the literal sense of the medical term "purgative." According to the medical view which we have already found influencing his ethical doctrine, health consists in the maintenance of an equality between the various ingredients of the body. Every now and again it happens that there arise superfluous accretions of some one ingredient, which are not carried away in the normal routine of bodily life. These give rise to serious derangement of function and may permanently injure the working of the organism, unless they are removed in time by a medicine which acts as a purge, and clears the body of a superfluous accumulation. The same thing also happens in the life of the soul. So long as we are in good spiritual health our various feelings and emotional moods will be readily discharged in action, in the course of our daily life. But there is always the possibility of an excessive accumulation of emotional "moods" for which the routine of daily life does not provide an adequate discharge in action. Unless this tendency is checked we may contract