This is an excerpt of a John Cage piece. I believe it's called Variations V from 1965. It includes Merce Cunningham among the performers.
Ubu.com also has a great excerpt of Septet from 1964, along with videos of a couple other performance excerpts and some audio recordings of him talking.
Both of these men were instrumental figures among a generation of artists that fundamentally transformed our ways of seeing and experiencing a world becoming that has become "contemporary". One that be discerned from the romantic past world from which it was born . Both men represent prime dynamic models for the artistic investigation of the world around and the sensations we encounter. If there can be a visceral-conceptual manifestation of the theories developed in the realm of physics and philosophy, these two embody it. There's an empirical analysis behind their awareness of the elemental constitutions of dance and music that cuts to an elegant core of the essence of experiencing these media.
Cage quotes the French poet Rene Char, "each act is virgin, even the repeated one" and Eric Satie "experience is a form of paralysis" to emphasize the necessity of receiving each occurance, each moment, each vision free from the sufocating raiment of expectation borne of memory. There's no better paradigm to observe in the exercising of both the disciplines of Maykng and C,ng.
The program of some eight Events performed by the MCDC as part of its two year residency at Dia:Beacon constituted an extended series of essays that remixed the choreographer's career and set it into a dialogue with the atmosphere and artwork of the museum. This program at Dia was not the only thing the company or the man were doing for the past two years, but in its whole, it I imagine it will stand as Cunningham's summation of his own career
Those who attended the Dia Events, know what a privileged moment they able to witness.Last week in the NY Times, Alistair Macaulay reviewed the company's performance in Battery Park City on the day of Cunningham's death. Macaulay's article stated that the dance company will cease to be in two years as was stipulated by the composer, but the works will continue to be licensed. Along with the article on the Times site, you can see an excerpt of a biographical film by Charles Atlas.