In this account, Ulrich Im Hof describes the origins and development of Enlightenment ideas and traces their effects on European and North American thought, politics and society. The author begins with an account of 18th-century European and American intellectual, political and social life. He describes the universities, academies, salons and reading societies from which the principal ideas of the Enlightenment emerged - in philosophy, religion, economics and politics - and he examines their diffusion, interaction and influence. Professor Im Hof concludes by examining the progress of Enlightenment thought in the 19th century, the counter-movement of Romanticism and the degree to which reason and rationality continue to hold sway at the turn of the 20th century.