In this interview, William Davidon discusses his political and social activism and its relationship to his scientific career. Topics discussed include: Albert Einstein; Norman Thomas; Purdue University; Marvin Goldberger; University of Chicago; atmospheric atomic bomb testing; Cold War; JASON group; Federation of American Scientists; American Friends Service Committee; American Physical Society; Adlai Stevenson; Morton Hamermesh; Haverford College; Hans Ekstein; Fay Ajzenberg-Selove; Committee for Nonviolent Action (CNVA); Pugwash Conferences on Science and World Affairs; Science for the People; Russ Stetler; Society for Social Responsibility in Science (SSRS); Mal Benjamin; Vietnam War protests; A. J. Muste; Oscar Handlin; Dan Berrigan; Union of Concerned Scientists; Henry Kissinger.