Oliver Sacks has been described (by "The New York Times Book Review") as "one of the great clinical writers of the 20th century," and his books, including the medical classics Migraine and Awakenings, have been widely praised by critics from W. H. Auden to Harold Pinter to Doris Lessing. In his last book, "The Man Who Mistook His Wife For A Hat", Dr. Sacks undertook a fascinating journey into the world of the neurologically impaired, an exploration that Noel Perrin in the "Chicago Sun-Times" called "wise, compassionate, and very literate...the kind that restore(s) one's faith in humanity."Now, with "Seeing Voices", Dr. Sacks takes us into the world of the deaf, a world he explores with the same passion and insight that have illuminated other human conditions for his readers everywhere. "Seeing Voices" is a journey: a journey first into the history of deaf people, the (often outrageous) ways in which they were seen and treated in the past, and the new understanding that started to dawn in the eighteenth century; and a journey into the present situation of the deaf - a situation which, all too often, is still one of misunderstanding and mistreatment. Dr. Sacks writes of how he has come to see deaf people "in a new light, as a people, with a distinctive language, sensibility, and culture of their own."Indeed, it is only in the last ten years that the extraordinary and beautiful visual-gestural language of the deaf - Sign - has been fully recognized as a language, as linguistically complete, rich, and expressive as any spoken language, a language with its own distinctive basis in the brain. The one overwhelming peril for the deaf is to be kept from achieving language competence of any kind, to be denied access to both Sign and speech, and that tragedy is completely preventable by early exposure to Sign. Sign is also social and cultural. It lies at the heart of the many manifestations of "deaf consciousness" in the past twenty years, among them the remarkable uprising of the deaf students at Gallaudet University in 1988. The revolt gained international attention and showed the world decisively that deaf people have "come of age" and no longer want to be treated as "disabled." Dr. Sacks gives a vivid personal account of the revolt and ponders its implications for the future.All his encounters in the course of this exhilarating journey raise issues of surprising depth and richness which, though of paramount interest to deaf people and all concerned with them, also extend powerfully to the human condition in general.