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Quotes after 1984, posthumous published
                                    
Source: Art is no longer justifiable or setting the record straight, 2000, p. 66
                                        
                                        as quoted in Joseph Beuys and the Celtic Wor(l)d: A Language of Healing, by Victoria Walters, LIT Verlag Münster, 2012, p. 206 
Quotes after 1984, posthumous published
                                    
Source: Art is no longer justifiable or setting the record straight, 2000, p. 66-67
Source: 1920s, "Picasso Speaks" (1923), p. 315.
                                        
                                        Quote in an interview with , 1986; republished in: Joseph Beuys, Carin Kuoni. Joseph Beuys in America: Energy Plan for the Western Man. New York, 1993.pp. 169-170
Beuys refers in his quote to the so-called 'Silence of Marcel Duchamp', the period that Duchamp stopped creating art 
1980's
                                    
Source: George L. K. Morris, Willem De Kooning, Alexander Calder, Fritz Glarner, Robert Motherwell, Stuart Davis. " What Abstract Art Means to Me http://www.jstor.org/stable/4058250," in: The Bulletin of the Museum of Modern Art, Vol. 18, No. 3, (Spring, 1951), pp. 2-15
                                        
                                        Karen Smith et al. Ai Weiwei (Contemporary Artists (Phaidon), London: Phaidon Press, 2009. 
2000-09, 2009
                                    
'Joseph Kosuth: Introductory note by the American editor', in Art-Language Vol.1 Nr.2, Art & Language Press, Chipping Norton (February 1970), p.3.
                                        
                                        Daily Close-up, after the Flag, Roberta Brandes Gratz, New York Post, 30 December 1970, p. 25 
1970s
                                    
 
                            
                        
                        
                         
                            
                        
                        
                         
                            
                        
                        
                         
                            
                        
                        
                        