I am frankly embarrassed that most of my musical life has been spent in the search for new materials. The significance of new materials is that they represent, I believe, the incessant desire in our culture to explore the unknown. Before we know the unknown, it inflames our hearts. When we know it, the flame dies down, only to burst forth again at the thought of a new unknown. This desire has found expression in our culture in new materials, because our culture has its faith not in the peaceful center of the spirit but in an ever-hopeful projection onto things of our own desire for completion.