Although the intellectual movement called “The Enlightenment” is usually associated with the 18th century, its roots in fact go back much further. But before we explore those roots, we need to define the term. This is one of those rare historical movements which in fact named itself. Certain thinkers and writers, primarily in London and Paris, believed that they were more enlightened than their compatriots and set out to enlighten them.

They believed that human reason could be used to combat ignorance, superstition, and tyranny and to build a better world. Their principal targets were religion (embodied in France in the Catholic Church) and the domination of society by a hereditary aristocracy.

Background in Antiquity

To understand why this movement became so influential in the 18th century, it is important to go back in time. We could choose almost any starting point, but let us begin with the recovery of Aristotelian logic by Thomas Aquinas in the 13th century. In his hands the logical procedures so carefully laid out by the ancient Greek philosopher Aristotle were used to defend the dogmas of Christianity; and for the next couple of centuries, other thinkers pursued these goals to shore up every aspect of faith with logic. These thinkers were sometimes called “schoolmen” (more formally, “scholastics,”) and Voltaire frequently refers to them as “doctors,” by which he means “doctors of theology.”

Unfortunately for the Catholic Church, the tools of logic could not be confined to the uses it preferred. After all, they had been developed in Athens, in a pagan culture which had turned them on its own traditional beliefs. It was only a matter of time before later Europeans would do the same.

The Renaissance Humanists

In the 14th and 15th century there emerged in Italy and France a group of thinkers known as the “humanists.” The term did not then have the anti-religious associations it has in contemporary political debate. Almost all of them were practicing Catholics. They argued that the proper worship of God involved admiration of his creation, and in particular of that crown of creation: humanity. By celebrating the human race and its capacities they argued they were worshiping God more appropriately than gloomy priests and monks who harped on original sin and continuously called upon people to confess and humble themselves before the Almighty. Indeed, some of them claimed that humans were like God, created not only in his image, but with a share of his creative power. The painter, the architect, the musician, and the scholar, by exercising their intellectual powers, were fulfilling divine purposes.

This celebration of human capacity, though it was mixed in the Renaissance with elements of gloom and superstition (witchcraft trials flourished in this period as they never had during the Middle Ages), was to bestow a powerful legacy on Europeans. The goal of Renaissance humanists was to recapture some of the pride, breadth of spirit, and creativity of the ancient Greeks and Romans, to replicate their successes and go beyond them. Europeans developed the belief that tradition could and should be used to promote change. By cleaning and sharpening the tools of antiquity, they could reshape their own time.

Galileo Galilei, for instance, was to use the same sort of logic the schoolmen had used–reinforced with observation–to argue in 1632 for the Copernican notion that the earth rotates on its axis beneath the unmoving sun. The Church, and most particularly the Holy Inquisition, objected that the Bible clearly stated that the sun moved through the sky and denounced Galileo’s teachings, forcing him to recant (take back) what he had written and preventing him from teaching further. The Church’s triumph was a Pyrrhic victory, for though it could silence Galileo, it could not prevent the advance of science (though most of those advances would take place in Protestant northern Europe, out of the reach of the pope and his Inquisition).

But before Galileo’s time, in the 16th century, various humanists had begun to ask dangerous questions. François Rabelais, a French monk and physician influenced by Protestantism, but spurred on by his own rebelliousness, challenged the Church’s authority in his Gargantua and Pantagruel, ridiculing many religious doctrines as absurd.

Michel de Montaigne

Michel de Montaigne, in a much more quiet and modest but ultimately more subversive way, asked a single question over and over again in his Essays: “What do I know?” By this he meant that we have no right to impose on others dogmas which rest on cultural habit rather than absolute truth. Powerfully influenced by the discovery of thriving non-Christian cultures in places as far off as Brazil, he argued that morals may be to some degree relative. Who are Europeans to insist that Brazilian cannibals who merely consume dead human flesh instead of wasting it are morally inferior to Europeans who persecute and oppress those of whom they disapprove?

This shift toward cultural relativism, though it was based on scant understanding of the newly discovered peoples, was to continue to have a profound effect on European thought to the present day. Indeed, it is one of the hallmarks of the Enlightenment. Just as their predecessors had used the tools of antiquity to gain unprecedented freedom of inquiry, the Enlightenment thinkers used the examples of other cultures to gain the freedom to reshape not only their philosophies, but their societies. It was becoming clear that there was nothing inevitable about the European patterns of thought and living: there were many possible ways of being human, and doubtless new ones could be invented.

The other contribution of Montaigne to the Enlightenment stemmed from another aspect of his famous question: “What do I know?” If we cannot be certain that our values are God-given, then we have no right to impose them by force on others. Inquisitors, popes, and kings alike had no business enforcing adherence to particular religious or philosophical beliefs.

It is one of the great paradoxes of history that radical doubt was necessary for the new sort of certainty called “scientific.” The good scientist is the one is willing to test all assumptions, to challenge all traditional opinion, to get closer to the truth. If ultimate truth, such as was claimed by religious thinkers, was unattainable by scientists, so much the better. In a sense, the strength of science at its best is that it is always aware of its limits, aware that knowledge is always growing, always subject to change, never absolute. Because knowledge depends on evidence and reason, arbitrary authority can only be its enemy.

The 17th Century

René Descartes, in the 17th century, attempted to use reason as the schoolmen had, to shore up his faith; but much more rigorously than had been attempted before. He tried to begin with a blank slate, with the bare minimum of knowledge: the knowledge of his own existence (“I think, therefore I am”). From there he attempted to reason his way to a complete defense of Christianity, but to do so he committed so many logical faults that his successors over the centuries were to slowly disintegrate his gains, even finally challenging the notion of selfhood with which he had begun. The history of philosophy from his time to the early 20th century is partly the story of more and more ingenious logic proving less and less, until Ludwig Wittgenstein succeeded in undermining the very bases of philosophy itself.

But that is a story for a different course. Here we are concerned with early stages in the process in which it seemed that logic could be a powerful avenue to truth. To be sure, logic alone could be used to defend all sorts of absurd notions; and Enlightenment thinkers insisted on combining it with something they called “reason” which consisted of common sense, observation, and their own unacknowledged prejudices in favor of skepticism and freedom.

We have been focusing closely on a thin trickle of thought which traveled through an era otherwise dominated by dogma and fanaticism. The 17th century was torn by witch-hunts and wars of religion and imperial conquest. Protestants and Catholics denounced each other as followers of Satan, and people could be imprisoned for attending the wrong church, or for not attending any. All publications, whether pamphlets or scholarly volumes, were subject to prior censorship by both church and state, often working hand in hand. Slavery was widely practiced, especially in the colonial plantations of the Western Hemisphere, and its cruelties frequently defended by leading religious figures. The despotism of monarchs exercising far greater powers than any medieval king was supported by the doctrine of the “divine right of kings,” and scripture quoted to show that revolution was detested by God. Speakers of sedition or blasphemy quickly found themselves imprisoned, or even executed. Organizations which tried to challenge the twin authorities of church and state were banned. There had been plenty of intolerance and dogma to go around in the Middle Ages, but the emergence of the modern state made its tyranny much more efficient and powerful.

It was inevitable that sooner or later many Europeans would begin to weary of the repression and warfare carried out in the name of absolute truth. In addition, though Protestants had begun by making powerful critiques of Catholicism, they quickly turned their guns on each other, producing a bewildering array of churches each claiming the exclusive path to salvation. It was natural for people tossed from one demanding faith to another to wonder whether any of the churches deserved the authority they claimed, and to begin to prize the skepticism of Montaigne over the certainty of Luther or Calvin.

Meanwhile, there were other powerful forces at work in Europe: economic ones which were to interact profoundly with these intellectual trends.

The Political and Economic Background

During the late Middle Ages, peasants had begun to move from rural estates to the towns in search of increased freedom and prosperity. As trade and communication improved during the Renaissance, the ordinary town-dweller began to realize that things need not always go on as they had for centuries. New charters could be written, new governments formed, new laws passed, new businesses begun. Although each changed institution quickly tried to stabilize its power by claiming the support of tradition, the pressure for change continued to mount. It was not only contact with alien cultural patterns which influenced Europeans, it was the wealth brought back from Asia and the Americas which catapulted a new class of merchants into prominence, partially displacing the old aristocracy whose power had been rooted in the ownership of land. These merchants had their own ideas about the sort of world they wanted to inhabit, and they became major agents of change, in the arts, in government, and in the economy.

They were naturally convinced that their earnings were the result of their individual merit and hard work, unlike the inherited wealth of traditional aristocrats. Whereas individualism had been chiefly emphasized in the Renaissance by artists, especially visual artists, it now became a core value. The ability of individual effort to transform the world became a European dogma, lasting to this day.

But the chief obstacles to the reshaping of Europe by the merchant class were the same as those faced by the rationalist philosophers: absolutist kings and dogmatic churches. The struggle was complex and many-sided, with each participant absorbing many of the others’ values; but the general trend is clear: individualism, freedom and change replaced community, authority, and tradition as core European values. Religion survived, but weakened and often transformed almost beyond recognition; the monarchy was to dwindle over the course of the hundred years beginning in the mid-18th century to a pale shadow of its former self.

This is the background of the 18th-century Enlightenment. Europeans were changing, but Europe’s institutions were not keeping pace with that change. The Church insisted that it was the only source of truth, that all who lived outside its bounds were damned, while it was apparent to any reasonably sophisticated person that most human beings on earth were not and had never been Christians–yet they had built great and inspiring civilizations. Writers and speakers grew restive at the omnipresent censorship and sought whatever means they could to evade or even denounce it.

Most important, the middle classes–the bourgeoisie–were painfully aware that they were paying taxes to support a fabulously expensive aristocracy which contributed nothing of value to society (beyond, perhaps, its patronage of the arts, which the burghers of Holland had shown could be equally well exercised by themselves), and that those useless aristocrats were unwilling to share power with those who actually managed and–to their way of thinking,–created the national wealth. They were to find ready allies in France among the impoverished masses who may have lived and thought much like their ancestors, but who were all too aware that with each passing year they were paying higher and higher taxes to support a few thousand at Versailles in idle dissipation.

The Role of the Aristocrats

Interestingly, it was among those very idle aristocrats that the French Enlightenment philosophers were to find some of their earliest and most enthusiastic followers. Despite the fact that the Church and State were more often than not allied with each other, they were keenly aware of their differences. Even kings could on occasion be attracted by arguments which seemed to undermine the authority of the Church. The fact that the aristocrats were utterly unaware of the precariousness of their position also made them overconfident, interested in dabbling in the new ideas partly simply because they were new and exciting.

Voltaire moved easily in these aristocratic circles, dining at their tables, taking a titled mistress, corresponding with monarchs. He opposed tyranny and dogma, but he had no notion of reinventing that discredited Athenian folly, democracy. He had far too little faith in the ordinary person for that. What he did think was that educated and sophisticated persons could be brought to see through the exercise of their reason that the world could and should be greatly improved.

Rousseau vs. Voltaire

Not all Enlightenment thinkers were like Voltaire in this. His chief adversary was Jean-Jacques Rousseau, who distrusted the aristocrats not out of a thirst for change but because he believed they were betraying decent traditional values. He opposed the theater which was Voltaire’s lifeblood, shunned the aristocracy which Voltaire courted, and argued for something dangerously like democratic revolution. Whereas Voltaire argued that equality was impossible, Rousseau argued that inequality was not only unnatural, but that–when taken too far–it made decent government impossible. Whereas Voltaire charmed with his wit, Rousseau ponderously insisted on his correctness, even while contradicting himself. Whereas Voltaire insisted on the supremacy of the intellect, Rousseau emphasized the emotions, becoming a contributor to both the Enlightenment and its successor, romanticism. And whereas Voltaire endlessly repeated the same handful of core Enlightenment notions, Rousseau sparked off original thoughts in all directions: ideas about education, the family, government, the arts, and whatever else attracted his attention.

For all their personal differences, the two shared more values than they liked to acknowledge. They viewed absolute monarchy as dangerous and evil and rejected orthodox Christianity. Though Rousseau often struggled to seem more devout, he was almost as much a skeptic as Voltaire: the minimalist faith both shared was called “deism,” and it was eventually to transform European religion and have powerful influences on other aspects of society as well.

Across the border in Holland, the merchants, who exercised most political power, there made a successful industry out of publishing books that could not be printed in countries like France. Dissenting religious groups mounted radical attacks on Christian orthodoxy.

The Enlightenment in England

Meanwhile Great Britain had developed its own Enlightenment, fostered by thinkers like the English thinker John Locke, the Scot David Hume, and many others. England had anticipated the rest of Europe by deposing and decapitating its king back in the 17th century. Although the monarchy had eventually been restored, this experience created a certain openness toward change in many places that could not be entirely extinguished. English Protestantism struggled to express itself in ways that widened the limits of freedom of speech and press. Radical Quakers and Unitarians broke open old dogmas in ways that Voltaire was to find highly congenial when he found himself there in exile. The English and French Enlightenments exchanged influences through many channels, Voltaire not least among them.

Because England had gotten its revolution out of the way early, it was able to proceed more smoothly and gradually down the road to democracy; but English liberty was dynamite when transported to France, where resistance by church and state was fierce to the last possible moment. The result was ironically that while Britain remained saturated with class privilege and relatively pious, France was to become after its own revolution the most egalitarian and anticlerical state in Europe–at least in its ideals. The power of religion and the aristocracy diminished gradually in England; in France they were violently uprooted.

The Enlightenment in America

Meanwhile, across the Atlantic, many of the intellectual leaders of the American colonies were drawn to the Enlightenment. The colonies may have been founded by leaders of various dogmatic religious persuasions, but when it became necessary to unite against England, it was apparent that no one of them could prevail over the others, and that the most desirable course was to agree to disagree. Nothing more powerfully impelled the movement toward the separation of church and state than the realization that no one church could dominate this new state.

Many of the most distinguished leaders of the American revolution–Jefferson, Washington, Franklin, Paine–were powerfully influenced by English and–to a lesser extent–French Enlightenment thought. The God who underwrites the concept of equality in the Declaration of Independence is the same deist God Rousseau worshipped, not that venerated in the traditional churches which still supported and defended monarchies all over Europe. Jefferson and Franklin both spent time in France–a natural ally because it was a traditional enemy of England–absorbing the influence of the French Enlightenment. The language of natural law, of inherent freedoms, of self-determination which seeped so deeply into the American grain was the language of the Enlightenment, though often coated with a light glaze of traditional religion, what has been called our “civil religion.”

This is one reason that Americans should study the Enlightenment. It is in their bones. It has defined part of what they have dreamed of, what they aim to become. Separated geographically from most of the aristocrats against whom they were rebelling, their revolution was to be far less corrosive–and at first less influential–than that in France.

The Struggle in Europe

But we need to return to the beginning of the story, to Voltaire and his allies in France, struggling to assert the values of freedom and tolerance in a culture where the twin fortresses of monarchy and Church opposed almost everything they stood for. To oppose the monarchy openly would be fatal; the Church was an easier target. Protestantism had made religious controversy familiar. Voltaire could skillfully cite one Christian against another to make his arguments. One way to undermine the power of the Church was to undermine its credibility, and thus Voltaire devoted a great deal of his time to attacking the fundamentals of Christian belief: the inspiration of the Bible, the incarnation of God in Jesus Christ, the damnation of unbelievers. No doubt he relished this battle partly for its own sake, but he never lost sight of his central goal: the toppling of Church power to increase the freedom available to Europeans.

Voltaire was joined by a band of rebellious thinkers known as the philosophes: Charles de Montesquieu, Pierre Bayle, Jean d’Alembert, and many lesser lights. Although “philosophe” literally means “philosopher” we use the French word in English to designate this particular group of French 18th-century thinkers. Because Denis Diderot commissioned many of them to write for his influential Encyclopedia, they are also known as “the Encyclopedists.”

The Heritage of the Enlightenment

Today the Enlightenment is often viewed as a historical anomaly, a brief moment when a number of thinkers infatuated with reason vainly supposed that the perfect society could be built on common sense and tolerance, a fantasy which collapsed amid the Terror of the French Revolution and the triumphal sweep of Romanticism. Religious thinkers repeatedly proclaim the Enlightenment dead, Marxists denounce it for promoting the ideals and power of the bourgeoisie at the expense of the working classes, postcolonial critics reject its idealization of specifically European notions as universal truths, and postructuralists reject its entire concept of rational thought.

Yet in many ways, the Enlightenment has never been more alive. The notions of human rights it developed are powerfully attractive to oppressed peoples everywhere, who appeal to the same notion of natural law that so inspired Voltaire and Jefferson. Wherever religious conflicts erupt, mutual religious tolerance is counseled as a solution. Rousseau’s notions of self-rule are ideals so universal that the worst tyrant has to disguise his tyrannies by claiming to be acting on their behalf. European these ideas may be, but they have also become global. Whatever their limits, they have formed the consensus of international ideals by which modern states are judged.

If our world seems little closer to perfection than that of 18th-century France, that is partly due to our failure to appreciate gains we take for granted. But it is also the case that many of the enemies of the Enlightenment are demolishing a straw man: it was never as simple-mindedly optimistic as it has often been portrayed. Certainly Voltaire was no facile optimist. He distrusted utopianism, instead trying to cajole Europeans out of their more harmful stupidities. Whether we acknowledge his influence or not, we still think today more like him than like his enemies.

As we go through his most influential work, The Philosophical Dictionary, look for passages which helped lay the groundwork for modern patterns of thought. Look also for passages which still seem challenging, pieces of arguments that continue today.

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