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 distinctiveness of self-evident propositions — to establish true and justified propositions despite having adopted a method of generalized doubt. As a consequence of this demonstration, Descartes considers science and mathematics to be justified to the extent that their proposals are established on a similarly immediate clarity, distinctiveness, and self-evidence that presents itself to the mind. The originality of Descartes's thinking, therefore, is not so much in expressing the "cogito" — a feat accomplished by other predecessors, as we shall see — but on using the "cogito" as demonstrating the most fundamental epistemological principle, that science and mathematics are justified by