A philosopher and historian of ideas, Arthur O. Lovejoy was largely responsible for the acceptance of intellectual history as a separate discipline. He cofounded with Philip P. Wiener The Journal of the History of Ideas in 1940. Lovejoy's professional career combined academic philosophy and extraordinary service to both academic life and his country. He was an early advocate of academic freedom, a founder of the American Association of University Professors (AAUP), and an articulate defender of American engagement in two world wars. True to the pragmatic tradition, Lovejoy in his engagement as a public intellectual rejected moral absolutes. He sought to combine academic freedom with a rejection of communism as an ideology opposed to freedom; a love of peace with an awareness of the importance of military engagement with violators of human rights. Lovejoy's 1927 Paul Carus Lectures for the American Philosophical Association (APA) were published in 1930 as The Revolt...