John Locke (1632-1704) was an English philosopher. Locke is considered the first of the British Empiricists, but is equally important to social contract theory. His ideas had enormous influence on the development of epistemology and political philosophy, and he is widely regarded as one of the most influential Enlightenment thinkers and contributors to liberal theory. His writings influenced Voltaire and Rousseau, many Scottish Enlightenment thinkers, as well as the American revolutionaries. This influence is reflected in the American Declaration of Independence. Locke's theory of mind is often cited as the origin for modern conceptions of identity and "the self", figuring prominently in the later works of philosophers such as David Hume, Jean- Jacques Rousseau and Immanuel Kant. He exercised a profound influence on philosophy and politics, in particular on liberalism. Most modern libertarians claim him as an influence. He was a strong influence on Voltaire, while his arguments concerning liberty and the social contract later influenced the written works of Alexander Hamilton, James Madison, Thomas Jefferson. His works include: Second Treatise of Government (1690) and An Essay Concerning Humane Understanding (1690).