Name given to the French version of the most important movement of ideas during the eighteenth century. Other versions appeared mainly in Germany, Scotland, and the United States, and there were individual thinkers who were accepted as members from all over Europe. Although there were some differences between them, the Enlightenment was a self‐consciously international, and more particularly European, movement. Europe was often seen as a single country divided into various provinces, but with a common way of thinking, a common set of values, and a common language, French, which had the same role as Latin in the Middle Ages. Belief in progress was universal among the thinkers of the Enlightenment, but it was not something that would appear by itself: they knew that they had to work for it. The word ‘civilization’, with its modern signification and values, was probably first used by Mirabeau (father of the French revolutionary figure) in 1757. Attempts to provide exact dates for the beginning or the end are little more than an imposed neatness. The origins of all Enlightenment thought can be found in the works of seventeenth‐century thinkers such as Hobbes, Descartes, Locke, and Newton, who were far more original than their later followers, and provided them with basic assumptions and methods in epistemology, psychology, natural science, and the study of society.
After the Glorious Revolution of 1688, which provided a new model for political change, the thought of its liberal supporters became the starting point for discussion in Europe in the early part of the eighteenth century. In the middle of the century came an explosion of ideas with Montesquieu's Esprit des lois (1748), the first volumes of the Encyclopédie (1751), Voltaire's Le Siècle de Louis XIV (1751), the start of Buffon's Histoire naturelle (1749) and, even if they belonged to a different style of thought, Rousseau's two Discourses (1750 and 1754).
Thinkers of the French Enlightenment were by no means agreed in many areas but they all rejected authority as the basis for knowledge. Instead they accepted the rationalism developed in the previous century, whether in its deductive or empirical form. This did not automatically imply a rejection of religion, and various positions were held including atheism, deism, various forms of Protestantism, and even Catholicism. In practice, however, it meant rejecting the Church as the source of knowledge and therefore of the rules by which anyone should live. These could only be reached by the individual exercising his reason. The best example of this attitude was the Encyclopédie, edited by Diderot and d'Alembert, which claimed to present all existing knowledge in an easily assimilable and usable form. This approach was applied to every subject, and included not only human nature, religion, and politics but also natural sciences, law, and the arts, as well as strictly practical subjects. Philosophy in a strict sense, especially ontology, suffered a decline.
Given this common starting point, the French Enlightenment was politically divided between those such as Voltaire who favoured strengthening the absolute monarchy as the most efficient way to achieve reform, and those such as Montesquieu who favoured restricting the monarchy to re‐establish liberty. Various other positions existed, such as those of Helvétius and Holbach. Neither side proposed extreme change although their thought has often been seen as a factor leading to the French Revolution. This was certainly not intended or foreseen, and the adherence of various absolute monarchs and other rulers in Europe, such as Frederick II of Prussia, Joseph II of Austria, and Catherine II of Russia, demonstrates the point. Rousseau is sometimes seen as a member of the French Enlightenment—he was for a time accepted by some of its other members and contributed to the Encyclopédie—but his romanticism and (sometimes) irrationalism make this doubtful.