Marcel duchamp urinal meaning guitar

The use of the wordfor the art movement, the meaning (if any) and intention of both the piece and the signature R.
The original, which is lost, consisted of a standard urinal, usually presented on its back for exhibition purposes rather than upright, and was signed and dated ‘R.
Marcel Duchamp kicked it all off by submitted a urinal to an art exhibit.

Guitar” (1913) reminds us of hierarchical judgments—good, better, best—which the evangelically pluralist “On Line” is at pains to dismiss.
In its original meaning, a ____ was a full-scale preliminary drawing executed on paper for projects such as frescoes, stained glass, oil paintings, or tapestries.