In the American Jungle by Waldo David Frank

It is revealing that the notion of "art for art's sake," of art sprung from itself and for itself, arose with the utilitarianism of the nineteenth century. If you will read the conversations of Goethe, the prefaces of Racine, the notebooks of Leonardo, the prose works of Dante, and finally trace back to Aristotle and to Plato, you may marvel (if you are a "modern") at the ethical bias in all our classic art. Not alone Milton believed that he was writing "to justify the ways of God to men. " It is safe to say that if a respectable goldsmith of the Renaissance had been cornered for a "reason" for his work, he would have professed some moral or some religious purpose not too remote from that which moved the Alexandrians and the prophets. While theology was hale, esthetics was its handmaid. Later, art went into the service of the God of Reason; and later still, took on the harness of metaphysics when that logic had assumed the imperatives of revealed religion. Only when modern man has debauched the ideal of spiritual progress-old as the Hindus and the Hebrews-to a bare functional or mechanistic pattern do we come upon art so divinely considered that it may have no "purpose."

The reason for this is not far to seek. While man's fate was still linked with gods or with godlike values, the arts could honorably serve. When that fate was mechanized into some economic or utilitarian or biological "design," art rebelled and set up a church of its own. The dogma of "pure poetry" and of "art for art's sake" is a reaction from the dogma of vulgar materialism and of "man for his belly's sake. " Being a reaction, it partakes of the nature of the source whence, however obscurely, it has risen.