The Age of Enlightenment refers to the 18th century in European philosophy, and is often thought of as part of a larger period which includes the Age of Reason.
The term also more specifically refers to an intellectual movement, "The Enlightenment," which is described as being the use of rationality to establish an authoritative ethics, aesthetics, and knowledge. This movement's leaders viewed themselves as a courageous, elite body of intellectuals who were leading the world toward progress, out of a long period of irrationality, superstition, and tyranny which began during a historical period they called the "Dark Ages". This movement provided a framework for the American and French Revolutions, as well as the rise of capitalism and the birth of socialism. It is matched by the high baroque era in music, and the neo-classical period in the arts.
Another important movement in 18th century philosophy, closely related to it, was a focus on belief and piety. Often rationalism was used to demonstrate the existence of a supreme being. Piety and belief were an integral part of the exploration of natural philosophy and ethics as well as political theories of the age. At the same time, prominent Enlightenment philosophers such as Voltaire and Jean-Jacques Rousseau questioned and attacked existing institutions of both Church and State.
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