George Quasha · CC BY 3.0

A founding figure of Conceptual Art in the 1960s, he treated language itself as a sculptural medium, presenting the same piece as wall text, printed catalog copy, or spoken performance and insisting there was no correct way to build the resulting work. He held that art should be non-metaphorical, a stance summarized in his own declaration that art is "a representation of an empirical existing fact."