A third result of the imitation of the classics was the development of applied, or concrete, criticism. If the foundations of literature, if the formation of style, can result only from a close and judicious imitation of classical literature, this problem confronts us: Which classical authors are we to imitate? An answer to this question involves the application of concrete criticism. A reason must be given for one's preferences; in other words, they must be justified on principle. The literary controversies of the humanists, the disputes on the subject of imitation, of Ciceronianism, and what not, all tended in this direction. The judgment of authors was dependent more or less on individual impressions. But the longer these controversies continued, the nearer was the approach to a literary criticism, justified by appeals to general principles, which became more and more fixed and determined; so that the growth of principles, or criteria of judgment in matters of literature, is in reality coterminous with the history of the growth of classicism.[256] But one of the most important consequences of the imitation of the classics was that this imitation became a dogma of criticism, and radically changed the relations of art and nature in so far as they touch letters and literary criticism. The imitation of the classics became, in a word, the basis of literary creation. Vida, for example, affirms that the poet must imitate classical literature, for only by such imitation is perfection attainable in modern poetry. In fact, this notion is carried to such an extreme that the highest originality becomes for Vida merely the ingenious translation of passages from the classic poets:-- "Haud minor est adeo virtus, si te audit Apollo, Inventa Argivum in patriam convertere vocem, Quam si tute aliquid intactum inveneris ante."[257] Muzio, echoing Horace, urges the poet to study the classics by day and by night; and Scaliger, as has been seen, makes all literary creation depend ultimately on judicious imitation: "Nemo est qui non aliquid de Echo." As a result, imitation gradually acquired a specialized and almost esoteric meaning, and became in this sense the starting-point of all the educational theories of the later humanists. The doctrine of imitation set forth by John Sturm, the Strasburg humanist, was particularly influential.[258] According to Sturm, imitation is not the servile copying of words and phrases; it is "a vehement and artistic application of mind," which judiciously uses and transfigures all that it imitates. Sturm's theory of imitation is not entirely original, but comes through Agricola and Melanchthon from Quintilian.[259] Quintilian had said that the greater part of art consists in imitation; but for the humanists imitation became the chief and almost the only element of literary creation, since the literature of their own time seemed so vastly inferior to that of the ancients.