"... the first Cubist painting might be said to have attempted to evince some outlines as to what visual art is, whilst, obviously, being held out as a work of visual art. But the difference here is one of what shall be called 'the form of the work'. Initially what conceptual art seems to be doing is questioning the condition that seems to rigidly govern the form of visual art -that visual art remains visual."
January 1, 1970
https://en.wikiquote.org/wiki/Art-Language