An encyclopedic examination of an extraordinary life in science. Freelance writer Hager wastes little time on Linus Pauling's Oregon boyhood, moving straight to his astonishingly precocious career in chemistry and a string of achievements that spanned more than seven decades and broke the boundaries between chemistry, physics, and medical research. Pauling was a brilliant theorist, hurling out an idea and throwing himself after it rather than building carefully collected data into a logical framework. He was usually right, most notably in his work with molecular structure and the nature of the chemical bond, for which he won his first Nobel Prize in 1954. But he was sometimes spectacularly wrong, falling victim to a characteristic combination of ``hurry and hubris,'' as when he lost the race to define the structure of DNA to comparative newcomers Watson and Crick. In middle age, Pauling's wife and his own restless intellect led him into political activism, and his tireless lobbying to ban nuclear testing and define the dangers of fallout attracted both the unwelcome attention of the House Un-American Affairs Committee and the Nobel Peace Prize in 1963. Pauling lost much of his public support later in life, and most remember him for his stubborn insistence on the merits of vitamin C. Hager had Pauling's cooperation in his project, as did Ted and Ben Goertzel, another team of recent biographers (p. 1078), but the depth of Hager's work focuses a much stronger microscope on the intricacies of Pauling's life. But Hager defines himself up front as ``a Pauling enthusiast,'' and though he does not omit Pauling's less rational moments, the friendly portrait that emerges is one of a misunderstood hero whose most outrageous statements still contained a kernel of overlooked insight. A competent, exhaustive life of a complicated genius, and a reminder that the search for scientific truth is never unaffected by the personalities and politics of the searchers.