The Quaker movement, properly known as the Society of Friends, had its beginnings in 17th century England with George Fox (1624-91), whose form of worship was liturgically sparse, relying on silence and the inspiring movement of the Inner Light, the spiritual presence within each person which prompts him or her to speak. The Society of Friends has been strongly committed to pacifism. William Penn, a Quaker, was the founder of the Pennsylvania colony based on the Quaker principle of religious tolerance.