The improviser in music, dance, comedy, conversation must be at his or her best responding to the moment with pure novelty. You must be so aware of where you are that what comes out will not only be unforeseen, but essential. Too much rehearsal will ruin the improvised performance in no time, but it can take most of a lifetime to trust one’s tools enough to rise to the openness of the instant. The instrument should be a seamless conduit of our intentions, such that it brings the work of the mind to life in the play of the body the touch of the fingers, the dance of response, the shredding of all plans and designs. You will take yourself to places you never imagined were reachable. Only by stepping into emptiness can you fill the impossible with your work. The beauty in improvisation is that you can do more than you can calculate, can soar far beyond any notes or structures you might plan. It’s wonderful to be part of it, to forget whatever limits you might imagine to hold you. To create way past one’s ability to keep track of things, to be trained enough to be ready for anything, that is the way that life and art progresses together. You must be able to do things that are, quite simply, beyond your abilities. When you succeed, the abilities themselves move onward.
– David Rothenberg, “Spontaneous Effort: Improvisation and the Quest for Meaning”