But who'd have known that, a century later, urinals would have become a standard photographic subject? No doubt some of the photographers know of Duchamp, and some do not. Does an enterprising photographer need that kind of authorization to flick one of these things?
These days Art History 101 teaches us that Duchamp's "Fountain" was an answer to the question: What is art? Think about it; it's tricky, no? The problem comes when you try to define art by delineating the characteristics of the work of art. What makes it special. You can say, well, it's beautiful. But what's beauty? Not so easy to answer.
Why not look at it this way: It's not the characteristics of the object that make the work of art, it's the institution. Hang it in a museum and shazaaum! it's a work of art. Simple, no?