Cubism was, if not necessarily the most important, at least the most complete and radical artistic revolution since the Renaissance. New forms of society, changing patronage, varying geographic conditions, all these things have gone to produce over the past five hundred years a succession of different schools, different styles, different pictorial idioms. But none of these has so altered the principles, so shaken the foundations of Western painting as did Cubism. Indeed, from a visual point of view it is easier to bridge the three hundred and fifty years separating Impressionism from the High Renaissance than it is to bridge the fifty years that lie between Impressionism and Cubism. If social and historical factors can for a moment be forgotten, a portrait by Renoir will seem closer to a portrait by Raphael than it does to a Cubist portrait by Picasso.
Despite its revolutionary quality, and the sudden, explosive way in which it seemed, almost overnight, to come into being, Cubism owed, of course, much to the art of the preceding fifty years. While the Cubists reacted against the passion and expressionistic violence of Van Gogh and the impressionistic 'intimisme' and pretentious symbolism of the Nabis, they admired Seurat for his intellectual objectivity, his classical detachment and formal purity; several of the future Cubists began their artistic careers as Divisionists, that is to say as his successors. Gauguin, in an indirect fashion, was a powerful influence in the formation of Cubism, in so far as it was he, in the eyes of the young painters working in Paris in the early years of the twentieth century, who had been the true discoverer of the aesthetic worth of primitive art. A form of 'primitive' art, Negro sculpture, was, it will be seen, one of the main influences in the birth of Cubism in that it encouraged Picasso, both on an intellectual level and by its formal, abstract properties, to take stock afresh of traditional pictorial values. In a more general way primitive art -- and here one can extend the term to include the work of that great 'primitive' painter, the Douanier Rousseau -- supported the Cubists in their determination to shake themselves free of what Braque has called 'la fausse tradition', the conventions that had governed Western painting for the preceding five centuries. Only one nineteenth-century artist, however, played a