Marcel Duchamp
[Artist, b. 1887, Blainville, France, d. 1968, Neilly-sur-Seine, France.]
It’s the viewer that makes the work. 
You know exactly what I think of photography. I would like to see it make people despise painting until something else will make photography unbearable. (In a letter to Alfred Stieglitz) Unless a picture shocks, it is nothing. Without glue—Make an assembly of ‘readymades’ balanced one on top of the other and photograph them.
(Proposal)