A pupil of William James, whose Essays in Radical Empiricism he edited (1912), Perry became one of the leaders of the New Realism movement. Perry argued for a naturalistic theory of value and a New Realist theory of perception and knowledge. He wrote a celebrated biography of William James, which won the 1936 Pulitzer Prize for Biography or Autobiography, and proceeded to a revision of his critical approach to natural knowledge. An active member among a group of American New Realist philosophers, he elaborated around 1910 the program of new realism. However, he soon dissented from moral and spiritual ontology, and turned to a philosophy of disillusionment. Perry was an advocate of a militant democracy: in his words "total but not totalitarian". Puritanism and Democracy (1944) is a famous wartime attempt to reconcile two fundamental concepts in the origins of modern America. In 1946-8 he delivered in Glasgow his Gifford Lectures, titled Realms of Value.
He married Rachel Berenson, and they lived in Cambridge. Their son was Edward Barton Perry born at their home 5 Avon Street in Cambridge, 27 Sept. 1906. Edward married in 1932 Harriet Armington Seelye (born Worcester, Massachusetts, 28 May, 1909, daughter of physician and surgeon Dr. Walker Clarke Seelye of Worcester and Annie Ide Barrows Seelye, formerly of Providence, Rhode Island.
Present Philosophical Tendencies: A Critical Survey of Naturalism, Idealism, Pragmatism, and Realism, together with a Synopsis of the Philosophy of William James, (1912), New York:Longmans, Green & Co.