8.9 — The Enlightenment

On 1 November 1755, All Saints' Day, an earthquake destroyed Lisbon while the churches were full. A tsunami followed, and then fire. Tens of thousands died, and the destruction fell on one of Europe's most devoutly Catholic capitals, at prayer, on a holy day.

The question everyone asked was why God had permitted it, and the answers people gave defined a generation.

Voltaire wrote a poem attacking the comfortable doctrine that this is the best of all possible worlds and that apparent evils serve a hidden good, and then wrote Candide, in which that doctrine is destroyed by having a character repeat it through one atrocity after another.

Rousseau replied to Voltaire that the earthquake was not a divine judgement but a consequence of human choices: people had built twenty thousand houses of six and seven storeys crowded together, and if they had lived dispersed the damage would have been far less.

And Kant, then a young lecturer, wrote three essays proposing physical causes — wrongly, as it happens, since he suggested underground gas — and in doing so treated the event as a natural phenomenon to be explained rather than a message to be interpreted.

Those three responses — moral outrage at unexamined doctrine, a social and material explanation, and a demand for a natural cause — are the Enlightenment in miniature.

What it was

A movement of the eighteenth century, centred in France, Scotland, England, the German states and the Netherlands, arguing that reason and evidence should be applied to human affairs as they had been to nature.

Kant's definition, from a short essay of 1784, is the best one. Enlightenment is humanity's emergence from its self-incurred immaturity — immaturity being the inability to use one's own understanding without the guidance of another. Self-incurred, because the cause is not lack of intellect but lack of resolve. His motto for it: Sapere aude — dare to know.

Its characteristic targets were arbitrary authority in all forms: absolute monarchy, aristocratic privilege by birth, established churches with legal power, censorship, judicial torture, and the confusion of custom with justice.

Its characteristic tools were publication and argument — books, pamphlets, newspapers, coffee houses, and salons hosted largely by women, which were the period's principal venue for intellectual exchange.

The arguments that mattered

Government by consent

Thomas Hobbes (writing earlier, during the English civil war) argued that life without a state is a war of all against all, and that people therefore contract to give up their freedom to a sovereign in exchange for order. His conclusion is authoritarian; his method is not, because he derives the state's authority from the consent of individuals rather than from God or tradition. Once you have said that government rests on a contract, you have opened the question of what happens when it is broken.

John Locke answered it. People have natural rights to life, liberty and property that exist prior to government. Government exists to protect them and holds power in trust. If it violates that trust, the people may replace it. He also argued for religious toleration on the ground that belief cannot be compelled and that the state has no competence in the salvation of souls.

Locke's Second Treatise is the direct source of the American Declaration of Independence (Chapter 10.2), which changed "property" to "the pursuit of happiness".

Montesquieu analysed constitutions comparatively and argued for the separation of powers — legislative, executive and judicial in different hands, each checking the others. He drew on Rome (Chapter 5.3) and on his reading of the English constitution, which he somewhat misunderstood. The American constitution is built on his framework.

Rousseau argued that legitimate authority comes from the general will of the people, that sovereignty cannot be represented but must be exercised directly, and that a society's inequalities are the product of its institutions rather than of nature. The Social Contract opens with the line that man is born free and is everywhere in chains.

Rousseau is also the most dangerous of them and the criticism should be stated. The general will is not the same as the majority's opinion — it is what the people would want if they willed the common good — and if a person disagrees with it, Rousseau says they may be "forced to be free". That formulation has been used to justify a great deal, and the connection to the Terror (Chapter 10.3) and to later totalitarian claims to represent the people's true interest is a live argument among historians.

Law and punishment

Cesare Beccaria's On Crimes and Punishments (1764) is one of the most immediately effective books in this chapter. It argued against torture — on the ground that it produces confessions from the weak rather than truth — and against the death penalty, and for punishments that are proportionate, certain, prompt and public, on the reasoning that deterrence comes from certainty rather than severity.

It was translated everywhere and it worked. Judicial torture was abolished across most of Europe within a few decades, and Beccaria's principles are the foundation of modern criminal law.

Economics

Adam Smith's The Wealth of Nations (1776) is covered in Chapter 9.6. Its Enlightenment character is the method: an attempt to explain how a complex order arises without anyone directing it.

And Smith wrote an earlier book, The Theory of Moral Sentiments, on sympathy as the basis of morality, which is routinely ignored by people who quote the later one. He was a professor of moral philosophy who thought self-interest operated within a framework of social feeling and justice, and he was scathing about merchants conspiring against the public and about the East India Company (Chapter 6.16).

Knowledge itself

The Encyclopédie, edited by Diderot and d'Alembert, published in 28 volumes between 1751 and 1772, aimed to collect all human knowledge and — the political part — to change the way people think.

Its method was subversive by design. It treated crafts and manufacturing with the same seriousness as theology, described technical processes in detail with plates, and used cross-references to undermine articles it could not attack directly — a respectful entry on a religious doctrine cross-referenced to an article on superstition.

It was banned, its privilege revoked, and it was published anyway — with printers working under protection from officials who were sympathetic, which is the Chapter 8.8 fragmentation argument operating inside a single country.

David Hume made the most rigorous sceptical arguments of the period — on causation, that we observe regular succession and never necessity, so induction cannot be justified by reason; and on miracles, that testimony should only be believed when its falsehood would be more miraculous than the event reported.

The disagreements

Treating the Enlightenment as one position is a mistake, and the disagreements are where the interest is.

Voltaire and Rousseau despised each other. Voltaire favoured enlightened monarchy, urbanity and commerce; Rousseau distrusted civilisation itself and argued that the arts and sciences had corrupted morals.

Hume's scepticism cut against the confident rationalism of the French philosophes.

Burke, writing at the end of the period, attacked the French Revolution's attempt to rebuild society from abstract principles, arguing that institutions embody accumulated practical wisdom that no individual reasoner can reconstruct. His Reflections on the Revolution in France is the founding text of modern conservatism and it correctly predicted the Terror and the military dictatorship.

And Mary Wollstonecraft's A Vindication of the Rights of Woman (1792) turned the movement's own arguments on it: if reason is the ground of rights, and women have reason, then the exclusion of women is inconsistent. She also argued that the apparent inferiority of women was a product of their education, which is an Enlightenment argument in form and content.

The hypocrisies, stated plainly

This is the section the chapter needs.

Slavery. Locke, whose theory of natural rights founded the American Republic, invested in the Royal African Company and helped draft a constitution for Carolina that gave masters absolute power over their slaves. Jefferson wrote that all men are created equal and owned around six hundred people over his lifetime. Voltaire invested in the slave trade.

And several of them argued against it. Montesquieu ridiculed the justifications for slavery devastatingly. Condorcet argued for immediate abolition and for women's suffrage. Diderot attacked colonialism directly. The movement contained both, and pretending it contained only one is dishonest in either direction.

Racial theory. Hume wrote a footnote asserting the natural inferiority of non-white peoples. Kant wrote on race in terms that are straightforwardly racist. The same intellectual apparatus that produced universal rights also produced the first systematic attempts to classify humanity into a hierarchy of races, and the second was used to justify empire for the next two centuries.

Colonialism. Enlightenment ideas of progress and civilisation supplied the justification for colonial rule — the argument that some peoples were not yet ready for self-government and required tutelage. Mill's essay On Liberty contains an explicit exemption for "barbarians", and Mill worked for the East India Company for thirty-five years.

Women. With few exceptions, the philosophes did not extend their arguments to women, and Rousseau's Émile prescribes an education for girls explicitly designed to make them pleasing to men.

How to hold this. The arguments are not invalidated by the failures of the people who made them — that is a genetic fallacy, and the arguments were used against those very failures by abolitionists, by Wollstonecraft, by the Haitian revolutionaries (Chapter 10.5), and by every anti-colonial movement including India's (Chapter 6.20). And the failures are not incidental: the same period produced the intellectual foundations of both universal rights and scientific racism, and understanding how requires holding both.

Where it landed

Directly into two revolutions. The American Declaration is Locke; the constitution is Montesquieu; the French Declaration of the Rights of Man and of the Citizen is the whole movement compressed into seventeen articles (Chapters 10.2 and 10.3).

Into legal reform — the abolition of torture, the codification of law, and eventually the Napoleonic Code, which spread across Europe and beyond.

Into abolition (Chapter 8.6), where the argument that all humans have the same rights had no defensible exception.

And into every anti-colonial movement afterwards, which used the coloniser's own stated principles as its strongest weapon (Chapter 6.20).

Where this shows up in your life

Every constitution in the world contains some version of these arguments: rights that precede the state, government by consent, separation of powers, equality before the law, freedom of conscience and of expression.

Your criminal justice system — proportionate punishment, the presumption of innocence, no torture, public trial — is Beccaria.

And the disposition is available to you directly. Kant's sapere aude is not a claim about the eighteenth century. It is an instruction: work it out yourself rather than accepting it because someone in a position of authority said it. Chapter 16.4 is the practical version.

What the next page covers

In 1600, the Ottoman, Safavid and Mughal empires were larger, richer and militarily stronger than any European state. By 1800 all three were in serious decline and two would be under European domination within a century. Chapter 8.10 asks why — examining each on its own terms, testing the standard explanations, and closing this Part with the honest question of how much of the divergence was institutional, how much was geographical, and how much was contingent.