William James: Be optimistic
Pessimism leads to weakness, optimism to power.
William James (New York January 11, 1842 - Chocorua NH August 26, 1910) was an American philosopher and psychologist who was also trained as a physician. The first educator to offer a psychology course in the United States. James was one of the leading thinkers of the late nineteenth century and is believed by many to be one of the most influential philosophers the United States has ever produced, while others have labelled him the "Father of American psychology". Along with Charles Sanders Pierce and John Dewey, he is considered to be one of the major figures associated with the philosophical school known as pragmatism, and is also cited as one of the founders of the functional psychology. William was the son of Henry James Sr. and older brother of the famous American writer Henry James.