In classic psychoanalytic style, Phillips strips our lives down to the fundamentals to illustrate the delicate balance between sanity and insanity. Sanity, he notes, "has never been a popular word, or indeed... a condition one might write a book about." Madness, on the other hand, is dramatic and all too visible. We have psychiatrists, neurologists and researchers dedicated to studying and treating madness, but not even a quantifiable definition of saneness. Deftly guiding readers through historical and literary uses of "sane" and "mad," Phillips cites Thomas Carlyle, R.D. Laing, Melanie Klein, D.W. Winnicott and Richard Dawkins, among others, to illustrate the stark absence of a definitive definition of sanity. In Hamlet, for instance, Polonius uses the word "madness" to describe Hamlet's inventiveness and eloquent intelligence: he admires Hamlet's madness. Phillips examines the presence and essence of madness in all aspects of modern life in intriguing and disturbingly frank chapters on the chaos of raising children, the turmoil of adolescence, sexual appetites and the pursuit of wealth. His arguments, both thought provoking and provocative, may affect future definitions of sanity and madness, and readers are left with a fresh awareness of what it really means to be sane.