John Locke (August 29, 1632-October 28, 1704) was a British philosopher and physician and one of the most influential of the Enlightenment thinkers. Locke's book Two Treatises of Government (1690) greatly influenced Thomas Jefferson in the writing of the Declaration of Independence. He believed that people by nature have certain rights, including life, liberty, and the ownership of property, and that all men are created equal. Locke's major work was An Essay Concerning Human Understanding (1690), which describes his theory of how the mind functions in learning about the world.