For if all knowledge of the natural world is conditioned by institutions of knowledge with their own particular and parochial ways of producing truth, then the real - Nature - is not so much that which appears in representation, as that which remains always outside it. If the primary habitat of human beings is the order of symbols and communication (the library), then nature can never be captured in any single representational system we may produce. The real exists as an excess lying beyond the scope of representation, as a reserve which the production of truth draws upon, but cannot exhaust or contain.

Norman Bryson, 'Mark Dion and the Birds of Antwerp' in Mark Dion, (Phaidon Press Limited, 1997) pp. 96-97

I have forced myself to contradict myself [...] in order to avoid conforming to my own taste.

Marcel Duchamp, Marcel Duchamp - The Art of Making Art In the Age of Mechanical Reproduction
(Harry N. Abrams Inc., 1999) p. 296

What would I do with money? I have enough for my needs... If I had more money I would have to spend time taking care of it and that is not the way I want to live.

Marcel Duchamp, Marcel Duchamp - The Art of Making Art In the Age of Mechanical Reproduction
(Harry N. Abrams Inc., 1999) p. 157