Ralph Barton Perry (July 3, 1876 in Poultney, Vermont – January 22, 1957 in Boston, Massachusetts) was an American philosopher. He was a strident moral idealist who stated in 1909 that, to him, idealism meant "to interpret life consistently with ethical, scientific, and metaphysical truth." Perry's viewpoints on religion stressed the notion that religious thinking possessed legitimacy should it exist within a framework accepting of human reason and social progress.
He was educated at Princeton (B.A., 1896) and at Harvard (M.A., 1897; Ph.D., 1899), where, after teaching philosophy for three years at Williams and Smith colleges, he was instructor (1902–05), assistant professor (1905–13), full professor (1913–30) and Edgar Pierce Professor of Philosophy (1930–46). He was president of the American Philosophical Association's eastern division in 1920–21.
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. Between 1946 and 1948, he delivered in Glasgow his Gifford Lectures, titled Realms of Value.
He married Rachel Berenson, and they lived in Cambridge, Massachusetts. Their son was Edward Barton Perry born at their home 5 Avon Street in Cambridge, 27 September 1906. In 1932, Edward married 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.
In 1919, he gave the commencement address for the first graduating class of Connecticut College, which had opened its doors in 1915.