The eighteenth century reviewed a bright, intellectual, intellectual perspective, in which it embodied the ideas of "good" and "humanity". The symbol of this era with its open flowers, and left behind a group of reform projects that came in the France revolution. In this book, Karl Baker reviews the political and social idea that prevailed in this century, relying on its historical method that is coherent and compatible until the maximum. "Enlightenment" and the spread of the values ​​of happiness, freedom, brotherhood and equality were the peak of philosophers' interest in this era, as the "Honorable City" controlled their ideas, and although it was not exclusively for the eighteenth century. This book is among the most important works that discussed the ideas of this century, as the author explained the influence of the philosophers of this period with historical heritage. Baker gave his book through four elaborate lectures in which he reviewed the philosophical, social and political framework for the eighteenth century.