In so far, on the other hand, as aesthetics is an attempt to define the purpose of art and so to formulate the standards presupposed in judgments of taste, it is closely related to criticism. The relation is essentially that between theory and the application of theory. It is the office of the critic to deepen and diffuse the appreciation of particular works of art. For this purpose he must possess standards; but he need not be, and in fact often is not, aware of them. A fine taste may serve his ends. Not infrequently, however, the critic endeavors to make clear to himself and his readers the principles he is employing. Now, on its normative side, aesthetics is ideally the complete rationale of criticism, the systematic achievement, for its own sake, of what the thoughtful critic attempts with less exactness and for the direct purpose of appreciation. It is beyond the province of aesthetics to criticize any particular work of art, except by way of illustration. The importance of illustration for the sake of explaining and proving general principles is, however, fundamental; for, as we have seen, a valuable aesthetic theory is impossible unless developed out of the primary aesthetic life of enjoyment and estimation, a life of contact with individual beautiful things. No amount of psychological skill in analysis or philosophical aptitude for definition can compensate for want of a real love of beauty,--of the possession of something of the artistic temperament. People who do not love art, yet study it from the outside, may contribute to our knowledge of it through isolated bits of analysis, but their interpretations of its more fundamental nature are always superficial. Hence, just as the wise critic will not neglect aesthetics, so the philosopher of art should be something of a critic. Yet the division of labor is clear enough. The critic devotes himself to the appreciation of some special contemporary or historical field of art--Shakespearean drama, Renaissance sculpture, Italian painting, for example; while the philosopher of art looks for general principles, and gives attention to individual works of art and historical movements only for the purpose of discovering and illustrating them. And, since the philosopher of art seeks a universal idea of art rather than an understanding of this or that particular work of art, an intimate acquaintance with a few examples, through which this idea can be revealed to the loving eye, is of more importance than a wide but superficial aesthetic culture.