More notes on nothing:

Georges Perec, famous for his novel A Void in which he writes a novel without any letter 'e' in it; with difficulty enough without then translation into english by Gilbert Adair, making a detective novel in which the search for a solution is paralleled by the missing letter. The underlying principle here and within the rest of the 'OULiPo' group was to investigate the creative possibilities offered by incorporating mathematical structures and other forms of artificial restriction into literature - rejecting structuralism for 'structurElism' as they put it. 

But what if the medium is the message and all that is left is the void?
In Erased de Kooning Drawing, of 1953, Rauschenberg literally erased a drawing by the famed Abstract Expressionist Willem de Kooning, thereby removing its aesthetic content. He had considered using one of his own images but realised that in this case "the work would return to nothing" (Robert Rauschenberg, Smithsonian Institute catalogue, 1976). In other words, it was important that the drawing already had a commodity value and would be physically difficult to rub out such that the act of erasing it would be arduous and be a symbolic rejection of  'formalist commodity-making'. 
He said he was trying "... to purge myself of my teaching and at the same time exercise the possibilities - so I was doing monochrome no-image" (also in catalogue, p.75).

Such an example of unmaking an artwork is rooted in zero-action events and auto-destructive art (and for that matter its inverse: the auto-generative art object as the object that makes itself automatically, cf. autonomy/autobiography). The most clear example of zero-action is perhaps the no performed sound or silence of John Cage's '4'33'. The performer, who simply sits quietly in front of the piano for four minutes and thirty-three seconds, merely opens and closes the piano lid to indicate the piece's three 'movements'. 

The performance, of course, clearly consists of something - ambient sound, the sounds of bodies and spaces, breathing, mumbling, just ordinary noise. The audience is encouraged to reflect upon the 'framing' devices of the work of art and consider the background more fully.

Likewise, Merce Cunningham treated all movements of the body as potential dance movement - use of chance to determine choreography (now uses computers to generate choreography).
Despite the critique of everyday life (cf. Society of the Spectacle and the Situationist international), Cage is a quietist - in that he did not demand political change, only against established value judgement.

It might be concluded that in this kind of work 'Everything equals nothing and that art is equivalent to nothing'. On the contrary, the performance, of course, clearly consists of something. The audience is encouraged to reflect upon the 'mediating' devices of the work of art and consider the distinction between presentation and representation (and the noisiness of silence). 
This non-action emphasises that nothing is an echo of something, or in this case, as Cage put it: "Every something is an echo of Nothing" (from, John Cage, "Silence", from Lecture on Something, p.131, quoted in Frances Dyson, "The Ear That Would Hear Sounds In Themselves", in, Kahn & Whitehead, Wireless Imagination, p.383).

The void of  zero-action attempts to remove representation and signifying practices but is knowingly (or is it annoyingly) aware of its necessary failure. The point being that there is no emptiness as such, only context and the medium employed as the message and ultimately as the art object/event. Furthermore, as an object/event, its meaning is activated by the presence of a viewer through a 'making-event' (John Latham's phrase, from Dialogues with the Machine, ICA conference, June 1998 - although as he distinguishes between a 'making-event'  and 'viewing -event'). The audience is encouraged to become the artist to fill the void (of meaning). The viewer makes the work through granting it meaning reinscribing it with detail.

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There are many examples of nothing as art, including Picabia and Duchamp of course, but also: John Baldessari cremated all his work from May 1953 to March 1966 to give himself a fresh start; Kozlov showed an empty film reel; Keith Arnatt titled a work 'Is it possible for me to do nothing as my contribution to this exhibition?'; Barry even closed the gallery for one of his shows; carnevale welcomed visitors to a totally empty room; and so on and so forth (all quoted in Lippard, 1997: xx).