William James came from one of the most famous families in the history of American culture. His father was a philosopher and an acquaintance of Ralph Waldo Emerson. James's brother, Henry, was one of the greatest novelists in American history.

James had a lively prose style and was a prolific thinker who wrote on a wide range of topics. Early in his career he wrote an influential book on psychology, Principles of Psychology He also wrote an interesting book on religion, Varieties of Religious Experience, and always was interested in occult phenomena such as ghosts and ESP.

While he was a professor at Harvard during the early 20th century, James popularized Pragmatism in several short essays and lectures.