26 The Enlightenment

The Enlightenment is the name given to the era of intellectual and critical ferment that began in Europe and America in the late 17th century and continued through the century that followed. During this period a diverse range of thinkers—known as the philosophes in France—sought to replace the blindly accepted beliefs of the past with rational thought and rational practice—in everything from political economy to the treatment of criminals.

The thinkers of the Enlightenment shared no coherent program, and indeed many were in disagreement with each other, but all sought to challenge the hitherto unquestioned assumptions of tradition and prejudice, and aspired to lead humanity out of the dark of superstition and into the light of reason. Their outlook was broadly liberal and humanitarian, and in general they were critical of the repressiveness and dogmatism of the Roman Catholic Church, and condemned those rulers who displayed a disregard for the welfare of their subjects.

The primacy of reason The thinkers of the Enlightenment looked back to the Scientific Revolution of the 16th and 17th centuries as their inspiration. Copernicus, Kepler, Galileo and others had demonstrated the falsity of the church’s teaching that the Earth was at the center of the universe, and Newton had, by inference from observations, come up with a complete explanation of motion, from that of a cannon ball through the air to a planet orbiting the Sun. This and other advances in experimental science in the later 17th century—which had both explanatory and predictive power—led to the triumph of empiricism over Cartesianism, the system of the French philosopher René Descartes (1596–1650). Descartes held that all knowledge gained via the senses is unreliable, and all that we can know for certain must be deduced from the basic irrefutable premise, “I think therefore I am.” The principles of empiricism, which contradicted those of Cartesianism, were enunciated by the English philosopher John Locke in his Essay Concerning Human Understanding (1690). In this, Locke argued that humans have no innate ideas, but derive all knowledge from experience, via “sensation” and “reflection.” This was what constitutes reason, he argued, “as contra-distinguished to Faith.”

Few of the thinkers of the Enlightenment were out-and-out atheists, but many were adherents of deism. Deists rejected the divine revelations and miracles of Christianity, proposing a God whose existence could be established by reason, rather than surmised by faith. Thus God was necessary as the “first cause” that brought the universe into being, and it was God who had designed the stars and the planets to run like clockwork in the way described by Newton. This God had endowed humans with reason and free will, but otherwise stood back from his creation.

“Écrasez l’infâme—[stamp out abuses]”

Voltaire, letter to M. d’Alembert, November 28, 1762

The influence of the Enlightenment The ideas of the Enlightenment were spread amongst the intellectual elites of Europe and America by works such as Voltaire’s Philosophical Letters on the English (1734), which discussed the ideas of Newton and Locke and expressed admiration for British liberties—in contrast to the autocracy of the ancien régime in his native France. The most important repository of Enlightenment thought, however, was the 28-volume French Encyclopédie, compiled under the direction of Denis Diderot between 1751 and 1772, which contained all the latest scientific and philosophical developments.

Some leading figures of the Enlightenment

·         John Locke (1632–1704), English philosopher: popularized the idea of the “social contract” between government and governed, and championed empiricism—the belief that knowledge is ultimately derived via the senses.

·         Voltaire (François-Marie Arouet, 1694–1778), French writer and philosopher: popularized ideas of Locke and Newton; champion of liberty and toleration; known especially for his satirical novella Candide.

·         Denis Diderot (1713–84), French philosopher: editor of and principal contributor to the Encyclopédie (1751–72); opponent of Christianity and proponent of materialism.

·         Montesquieu (Charles Louis de Secondat, Baron de Montesquieu, 1689–1755), French philosopher and writer: his Esprit des lois(Spirit of the Laws, 1748) showed how systems of law and government varied from society to society, giving rise to the concept of cultural relativism.

·         Cesare Beccaria (1738–94), Italian legal theorist: his Crimes and Punishments (1764) expounded the principles behind criminal law, called for the abolition of torture and capital punishment, and inspired many countries to reform their penal codes.

·         David Hume (1711–76), Scottish philosopher and historian: continuing in the empiricist tradition, he rejected the existence of innate ideas, examined the psychological basis of human nature, and applied an extreme skepticism to everything from supposed miracles to the concept of cause and effect, which he regarded as a “constant conjunction” rather than a logical inevitability.

·         Adam Smith (1723–90), Scottish philosopher and economist: in The Wealth of Nations (1776) he espoused free trade as against monopoly and regulation, upheld the role of self-interest in the creation of a wealthier society, and demonstrated the economic advantages of the division of labor.

·         Jean-Jacques Rousseau (1712–78), French philosopher and writer: he held that human nature is innately good, but spoiled by corrupt society. He increasingly opposed rationalism, championing the primacy of individual feeling.

Among those taken with the fashionable ideas of the philosophes were a number of Europe’s autocratic monarchs, including Catherine the Great of Russia, Frederick the Great of Prussia and Joseph II of Austria. All of these “enlightened despots” sought to impose “rational” reforms in their countries. There were limits to their enlightenment, however. Frederick may have liberalized the Prussian legal code and introduced social and economic reforms, but he also waged ruthless wars of conquest. Catherine too waged wars of territorial expansion, and abandoned her proposal to emancipate the serfs of Russia in the face of opposition by the serf-owners. Joseph did succeed in emancipating the serfs within the Holy Roman empire, but then proceeded to impose taxes on them. He also introduced religious toleration and reforms in education, the legal system and administration—some of which he had to withdraw in the face of opposition by certain groups whose privileges he threatened.

Of more enduring political consequence was the impact the language and ideas of Enlightenment thinkers had on some of the key documents of both the American and the French Revolutions, the American Declaration of Independence and the Bill of Rights. These documents include ideas that continue to dominate political discourse in Western liberal democracies: equality, individual rights, the idea that government only rules with the consent of the governed, religious toleration and due process of law.

the condensed idea

The Enlightenment helped to establish the values of modern liberal democracies