Charles Tart, who has written extensively on marijuana intoxication and other ways of scrambling the brain, herein proposes a theoretical framework for the notion that the mind has a number of available states of consciousness. Tart arbitrarily divides mental life into ten ""systems""--body awareness, external sense perception, emotion, judgment, and the like--each of which, he says, performs in a different but identifiable fashion when we are, say, drunk, meditating, or merely driving to the supermarket. This is all the author has to say, though his model is dressed up in the nattiest psychological jargon available--for ""d-SoC"" and ""d-ASC,"" two acronyms which plague the book, read ""discrete state of consciousness"" and ""discrete altered state of consciousness."" The jargon, plus Tart's annoying cant about the ""typical over-intellectualized Western academic,"" renders the book for the most part virtually unreadable. Tart's account of William, an experimental subject who was extraordinarily susceptible to hypnosis, has some intrinsic interest. Otherwise his pernicious vocabulary and his adulation of Don Juan, the Yaqui Indian mystic, predominate.