New York Dada known and controversial across the New York, as well as American in general, art scene. His personality was equally intoxicating as his art; according to Richter, "Duchamp's attitude is that life is a melancholy joke, an indecipherable non-sense, not worth the trouble of investigating. To his superior intelligence the total absurdity of life, the contingent nature of a world denuded of all values, are logical consequences of Descartes' Cogito ergo sum." Most famous amongst the works created by Duchamp in the New York period were his ready-mades, particularly the piece entitled "Fountain". During his time in New York he maintained
Cogito, ergo sum one's belief in their own existence would be secure, for there is no way one could be deceived unless one existed in order to be deceived. But I have convinced myself that there is absolutely nothing in the world, no sky, no earth, no minds, no bodies. Does it now follow that I, too, do not exist? No. If I convinced myself of something [or thought anything at all], then I certainly existed. But there is a deceiver of supreme power and cunning who deliberately and constantly deceives me. In that case, I, too, undoubtedly exist, if he deceives me;