1887-1968 1912-1992 1919-2009 1925-2008 1930- 1948- 20thcentury aesthetics alwin american anna art artanddance artisticcollaboration arts cage cunningham dance daniel duchamp elizabeth exhibitions existentialism experimentalmethods fenley friendsandassociatesduchamp jasper john johns kenneth king marcel mercecunninghamdancecompany modern moderndance molissa nagrin nikolais phenomenology philosophy rauschenberg robert sokolow streb unitedstates