During the 1870s, James participated in a discussion group that became known as “the Metaphysical Club.” Its members included Charles Sanders Peirce (1839–1914), U.S. Supreme Court Justice Oliver Wendell Holmes (1841–1935), and mathematician and philosopher Chauncey Wright (1830–1875). While the group was meeting, there was some concern on the part of civic leaders in New England that religion, particularly Protestantism, was suffering as a result of the popularity of Darwinism and intense interest in the sciences. At the time James began to teach philosophy, Harvard administrators had an interest in the potential of philosophy to support religion. When James began his career, the disciplinary boundaries between psychology and philosophy were fluid. Largely as the result of his work, the two fields were distinct by the end of his career. (To this day, William James Hall houses the Harvard Department of Psychology.)

Intellectually, James’ pragmatism grew out of the limitations of psychology to provide answers to the moral questions that interested him: How can religion be justified intellectually? Is there free will? What is the nature of truth?