William James (January 11, 1842 – August 26, 1910) was a pioneering American psychologist and philosopher. He wrote influential books on the young science of psychology, educational psychology, psychology of religious experience and mysticism, and the philosophy of pragmatism. He was the brother of novelist Henry James and of diarist Alice James.
James interacted with a wide array of writers and scholars throughout his life, including his godfather Ralph Waldo Emerson, Horace Greeley, William Cullen Bryant, Oliver Wendell Holmes, Jr., Charles Sanders Peirce, Josiah Royce, George Santayana, Ernst Mach, John Dewey, W.E.B. Du Bois, Helen Keller, Mark Twain, Horatio Alger, Jr., James Frazer, Henri Bergson, H. G. Wells, G. K. Chesterton, Sigmund Freud, Gertrude Stein, and Carl Jung.