There is an ever-increasing number of books on improvisation, ones that richly recount experiences in the heat of the creative moment, theorize on the essence of improvisation, and offer convincing arguments for improvisation’s impact across a wide range of human activity. This book is nothing like that. In a provocative and at times moving experiment, Gary Peters takes a different approach, turning the philosophy of improvisation upside-down and inside-out.             Guided by Kant, Hegel, Heidegger, and especially Deleuze—and exploring a range of artists from Hendrix to Borges—Peters illuminates new fundamentals about what, as an experience, improvisation truly is. As he shows, improvisation isn’t so much a genre, idiom, style, or technique—it’s a predicament we are thrown into, one we find ourselves in. The predicament, he shows, is a complex entwinement of choice and decision. The performativity of choice during improvisation may happen “in the moment,” but it is already determined by an a priori mode of decision. In this way, improvisation happens both within and around the actual moment, negotiating a simultaneous past, present, and future. Examining these and other often ignored dimensions of spontaneous creativity, Peters proposes a consistently challenging and rigorously argued new perspective on improvisation across an extraordinary range of disciplines.