[en] The memoirs of the author traces his life from his first-year graduate studies in physics at the University of Rochester in 1942 to his present position as Director of the University of California's Institute on Global Conflict and Cooperation. The part of his life involved in making weapons extends from 1942 to 1961. During this period, he worked with E.O. Lawrence on the Manhattan Project and served as director of Livermore after it became the Atomic Energy Commission's second nuclear weapons laboratory. He also served on many government advisory boards and commissions dealing with nuclear and other weapons. In 1961, the combination of a heart attack and changes in administration in Washington led York too return to the University of California for the talking peace portion of his life. He has since become a public exponent of arms control and disarmament and the futility of seeking increased security through more and better nuclear weapons. York's explanation of his move from making weapons to talking peace leaves the reader with a puzzle