Art is a part of life, but in order to be art it has to create for itself a separate zone... A urinal is not an art object as long as it is carrying out its essential function. To make it art we detach it from the plumbing, tip it on its end and set it on a plinth. The beholder then has to entertain a galaxy of new and unfamiliar thoughts about the object, redefining it and herself in relation to it. The original object, which Marcel Duchamp called Fountain, signing it R Mutt, was rejected by the Society of Independent Artists at whose New York gallery it was supposed to be exhibited in 1917 because, they said, it was not art. In 2004, 500 British “art experts” selected it as “the most influential artwork of the 20th century”.
-- Germaine Greer, “Now please pay attention everybody. I'm about to tell you what art is,” in The Guardian