Absolutism, the Scientific Revolution and the Enlightenment

Between roughly 1600 and 1789 Europeans rebuilt two things at once: the machinery of the state and the machinery of knowing. Kings who had once bargained with nobles, towns and provincial estates now taxed harder, drilled larger armies and claimed to answer to God alone — while in England and the Dutch Republic a different settlement gave law-making power to assemblies and made public credit, not royal glory, the sinew of power. In the same decades a small, quarrelsome network of astronomers, physicians and instrument-makers replaced Aristotle’s cosmos with a mathematical one, and then argued that the same methods could be turned on law, religion, punishment and trade. The result was the Enlightenment: not a single doctrine but an argument conducted in salons, coffeehouses and smuggled books. This chapter traces how power was concentrated, how it was checked, how nature was re-described, and what happened when reformers tried to govern by reason.

Section 1The Sinews of Power: Absolutism and Its Limits

What absolutism claimed

Absolutism is the doctrine that sovereignty is indivisible and rests wholly in the monarch, who is accountable to God rather than to any assembly, court or corporate body. Its clearest statement came from Jacques-Bénigne Bossuet, tutor to Louis XIV’s son, in Politics Drawn from the Very Words of Holy Scripture: the king’s person is sacred, his authority paternal, absolute and subject to reason. Behind Bossuet stood Jean Bodin, who in 1576 had defined sovereignty as the power to make law without consent, and Thomas Hobbes, who in Leviathan (1651) reached a similar conclusion from an entirely secular premise: without an undivided sovereign, life is a war of all against all.

The claim was a response to trauma. France had endured four decades of religious civil war, then the Fronde of 1648–1653, a tangled revolt of law courts and great nobles during which the boy king Louis XIV was hustled out of Paris in the night. He never forgot it. When Cardinal Mazarin died in 1661, the twenty-two-year-old announced that he would govern without a chief minister — and, remarkably for a man of his era, actually did the paperwork, meeting his councils several hours a day for fifty-four years.

The famous line L’état, c’est moi is almost certainly a later invention; what Louis is reliably reported to have said on his deathbed is closer to the opposite: Je m’en vais, mais l’État demeurera toujours — I depart, but the State will remain. That distinction matters. Absolutism was less a cult of personality than a theory of the state, and its practical content was administrative.

Building the fiscal-military state

What made the seventeenth-century monarchy formidable was money and men. Jean-Baptiste Colbert, controller-general of finances from 1665 until his death in 1683, attacked tax farming, audited accounts, chartered manufactures, subsidized the Gobelins tapestry works and the navy, and pursued mercantilism — the assumption that world trade was a fixed pot and that a state grew rich by exporting more than it imported. He also extended the intendants, royal commissioners posted to each généralité who reported directly to the royal council and could override local officials. The intendant, not Versailles’ mirrors, was the real innovation.

Meanwhile the army swelled from perhaps 70,000 men in the 1660s to over 340,000 on paper by the 1690s, with uniforms, standardized muskets, magazines and Vauban’s ring of frontier fortresses. Historians call this the fiscal-military state: a government whose primary business is extracting revenue to pay for war, and whose bureaucracy grows because war debts do. Louis fought in four major conflicts. The last, the War of the Spanish Succession (1701–1714), ended at Utrecht and Rastatt with his grandson on the Spanish throne but barred from ever inheriting France, and France itself exhausted, its people taxed through the taille, the gabelle salt monopoly and the new capitation head tax, and the famines of 1693–94 and 1709 killing well over a million people between them.

Versailles itself, occupied by the court from 1682, was a political instrument. By requiring the high nobility to attend the king’s rising and retiring, to compete for the right to hand him his shirt, Louis converted a warrior aristocracy into courtiers whose careers depended on visibility rather than on provincial armies. It worked, at a price: the nobles kept their fiscal exemptions, and the crown kept borrowing.

Variants: Prussia, Russia, Austria, Spain

The French model was copied unevenly. In Brandenburg-Prussia, Frederick William the Great Elector (1640–1688) struck a bargain that would define the state: the Junker nobility surrendered political resistance and paid little tax, and in exchange received unchallenged authority over their serfs plus, in time, a near-monopoly on officer commissions. His grandson Frederick William I (1713–1740) drilled an army of 80,000 out of a population of some 2.2 million, ran the treasury like a miser and created the General Directory. Prussia was, in a phrase usually credited to Mirabeau though its origin is disputed, not a state with an army but an army with a state.

In Russia, Peter the Great (r. 1682–1725) forced a top-down transformation: a new capital, St Petersburg, begun in 1703 on conquered marshland at enormous human cost; the beard tax and Western dress imposed on the service nobility; the Table of Ranks (1722) tying status to state service rather than birth; the patriarchate replaced by a Holy Synod under a lay procurator. Victory over Sweden at Poltava (1709) and the peace of Nystad (1721) made Russia a European great power. It also deepened serfdom exactly as western Europe was shedding it — the great east-west divergence of early modern Europe.

The Austrian Habsburgs ruled a composite monarchy of Austrian, Bohemian and Hungarian lands, each with its own laws and diets; after breaking the Ottoman siege of Vienna in 1683 and winning Hungary at Karlowitz (1699), they expanded outward but never centralized as thoroughly. Spain moved the other way. Burdened by American silver that fuelled inflation rather than industry, by the expulsion of the Moriscos and by chronic war, it lost Portugal in 1640, revolted in Catalonia, and by 1700 was a prize to be fought over rather than a power.

Section 2The Other Path: England, the Dutch and the Politics of Consent

Civil war, regicide and the failure of republican rule

England’s crown was chronically poor. Without a standing army or a professional bureaucracy, Stuart kings needed Parliament to vote taxes, and Parliament used the moment to press grievances. Charles I accepted the Petition of Right in 1628 — no taxation without parliamentary consent, no arbitrary imprisonment, no billeting of troops — then ruled without Parliament for eleven years, raising money through revived medieval devices such as ship money. The system held until he tried to impose an Anglican prayer book on Presbyterian Scotland in 1637. The Scots invaded; Charles needed money; the Long Parliament met in 1640 and never let go.

Civil war broke out in 1642. It was fought over religion as much as taxation, and it radicalized fast: at Putney in 1647 the New Model Army’s council, chaired by Oliver Cromwell, heard Colonel Thomas Rainsborough insist that “the poorest he that is in England hath a life to live as the greatest he.” In January 1649 a purged Parliament tried the king for treason against his own people and beheaded him — an act that horrified Europe precisely because it made the monarch a defendant. The republic that followed, and then Cromwell’s Protectorate (1653–1658), never solved the problem of legitimacy without a king. In 1660 Charles II was invited back.

The Restoration settlement papered over the real dispute: whether a Catholic could inherit. The Exclusion Crisis of 1679–1681 produced the labels Whig and Tory. When James II succeeded in 1685, suspended penal laws by royal prerogative, packed the army with Catholic officers and then fathered a Catholic heir in June 1688, seven leading men invited his Protestant son-in-law William of Orange to intervene.

1688 and its settlement

The Glorious Revolution was neither bloodless nor purely English — William landed with roughly 15,000 troops, and the accompanying wars in Ireland and Scotland were savage. But in England the outcome was constitutional. The Declaration and then the Bill of Rights (1689) barred the crown from suspending laws, keeping a standing army in peacetime or levying taxes without parliamentary consent, guaranteed free elections and free speech in Parliament, and excluded Catholics from the throne. The Toleration Act of the same year gave Protestant dissenters freedom of worship, though not full civil rights. The Act of Settlement (1701) secured judges’ tenure and the Hanoverian succession; the Union with Scotland followed in 1707.

John Locke’s Two Treatises of Government, published in 1689, was long read as the revolution’s official apology. Since Peter Laslett’s work most scholars date its composition a decade earlier, during the Exclusion Crisis, making it a justification for resistance rather than a rationalization of a fait accompli. Its argument is still the load-bearing one in liberal political thought: individuals possess natural rights to life, liberty and property; government is a trust created by consent to protect them; when a ruler breaks that trust, the people may replace him.

The practical payoff was financial. A monarch who could not repudiate debts unilaterally, whose budgets Parliament audited, was a better credit risk. The Bank of England (1694) and a funded national debt let Britain borrow at rates France could not match, which is how a smaller country outspent a larger one through a century of war. This is the great irony of the period: the constitutional state proved more powerful than the absolutist one, because consent was cheaper than coercion.

Republics that were not democracies

The Dutch Republic offered a third model: seven sovereign provinces, a States General that voted by province, no monarch, and a stadholder from the House of Orange who commanded the armed forces. Amsterdam merchants ran the richest economy in Europe on the back of the Baltic grain trade, the herring fishery, the Bank of Amsterdam (1609) and the Dutch East India Company (1602). Religious pluralism was pragmatic rather than principled — Catholics worshipped in “hidden churches,” Sephardic Jews found refuge, and Amsterdam’s presses printed what French censors banned, which is why so much of the century’s scientific and philosophical writing carries a Dutch imprint.

It is worth being blunt about the limits. The Dutch Republic was governed by a closed oligarchy of regent families; England’s post-1689 electorate was perhaps four or five percent of the population, and constituencies were wildly unequal. Neither was democratic in any modern sense. What they had was accountable government: rulers who could be checked, budgets that could be scrutinized, and a press that could not be silenced.

The counterexample is instructive. The Polish-Lithuanian Commonwealth had an elective monarchy and a Sejm in which any single deputy could annul an entire session by invoking the liberum veto, used destructively from 1652 onward. Liberty without an effective executive proved fatal: between 1772 and 1795 Russia, Prussia and Austria partitioned the Commonwealth out of existence. Consent had to be paired with capacity.

Section 3A New Way of Knowing: The Scientific Revolution

Breaking the closed cosmos

The inherited picture of the universe was Aristotle’s, refined by Ptolemy: a motionless Earth at the center, surrounded by nested crystalline spheres carrying the moon, sun, planets and fixed stars in perfect circles. Below the moon, things were made of earth, water, air and fire and were subject to change; above it, an unchanging fifth element. It was elegant, matched everyday experience and had been fused with Christian theology since the thirteenth century.

Nicolaus Copernicus, a Polish canon and physician, published On the Revolutions of the Heavenly Spheres in 1543, the year of his death. Putting the sun at the center explained the retrograde loops of the planets far more simply. But it created problems he could not answer: if the Earth moves, why is there no perceptible stellar parallax, and why are we not thrown off? Copernicus kept circles and epicycles, and his book was read for decades mainly as a calculating device.

Evidence accumulated from unexpected directions. Tycho Brahe, from his observatory Uraniborg, produced the most accurate naked-eye measurements ever made, and his observations of the new star of 1572 and the comet of 1577 showed changes above the moon and a path that should have shattered crystalline spheres. Johannes Kepler, using Tycho’s Mars data, abandoned circles altogether: planets travel in ellipses with the sun at one focus, sweep equal areas in equal times (1609), and their orbital periods relate to their distances by a fixed mathematical ratio (1619). Galileo Galilei turned a telescope on the sky from 1609 and found mountains on the moon, four satellites of Jupiter, sunspots and, late in 1610, the full cycle of phases of Venus — the last a direct refutation of the Ptolemaic arrangement, though not of Tycho’s compromise scheme.

Method, mathematics and the body

Two rival accounts of how to know emerged. Francis Bacon, in the Novum Organum (1620), argued for empiricism: systematic observation and controlled experiment, working upward from particulars, with the mind purged of its “idols” — the biases of language, tradition and self. René Descartes, in the Discourse on Method (1637), argued for rationalism: doubt everything doubtable until you reach an indubitable starting point, then deduce. His analytic geometry made curves algebraic, and his mechanical philosophy pictured the universe — and animal bodies — as matter in motion, obeying laws. Cartesian dualism, mind separate from an extended machine-like body, shaped medical thinking for centuries and still colors how clinicians talk about the “mind–body problem.”

Medicine supplied one of the era’s cleanest demonstrations. William Harvey, in De motu cordis (1628), used dissection, vivisection, ligature experiments on the arm and simple arithmetic — multiply stroke volume by heart rate and the blood pumped in an hour vastly exceeds body weight — to show that blood must circulate rather than being continuously manufactured and consumed as Galen had taught. He could not see the capillaries; Marcello Malpighi found them with a microscope in 1661. Robert Hooke’s Micrographia (1665) coined “cell,” and Antoni van Leeuwenhoek’s single-lens instruments revealed bacteria and protozoa in the 1670s. Robert Boyle, meanwhile, insisted chemistry describe matter as corpuscles rather than Aristotelian elements, and published the pressure–volume relation in 1662.

Isaac Newton’s Philosophiæ Naturalis Principia Mathematica (1687) closed the circle. Three laws of motion plus a single law of universal gravitation — every mass attracts every other in proportion to the product of the masses and inversely as the square of the distance — derived Kepler’s ellipses, the tides, the precession of the equinoxes and the path of comets from one principle. The same physics governed a falling apple and the moon. Newton candidly refused to explain what gravity is: hypotheses non fingo, I frame no hypotheses — a line he added to the second edition of 1713. Mathematical description that predicts, without a mechanical story, became the standard for science.

Who was allowed in the room

Discovery became durable because it became institutional. The Royal Society of London, founded in 1660 and chartered in 1662, adopted the motto Nullius in verba — take nobody’s word for it. Its secretary Henry Oldenburg launched the Philosophical Transactions in 1665, initially as his own venture, and it created something new: dated, credited, citable, criticizable publication. The Académie Royale des Sciences in Paris (1666) took the opposite approach, salaried and state-directed, aimed at maps, ballistics and engineering. Between them they established peer scrutiny, replication and priority disputes as the ordinary business of science.

Access was sharply bounded by sex and status. Margaret Cavendish, Duchess of Newcastle, published natural philosophy and visited the Royal Society in 1667 — as a spectacle, and no woman was elected to full fellowship until 1945. Maria Winkelmann-Kirch discovered a comet in 1702 while working in her husband’s Berlin observatory; after his death the Academy refused her the post on the grounds that it would set a precedent. Émilie du Châtelet translated the Principia into French with a commentary that remains the standard version; Laura Bassi held a chair at Bologna from 1732. Artisans, instrument-makers and apothecaries did essential work and are largely anonymous in the record.

Historians also disagree about the phrase itself. Herbert Butterfield popularized “the Scientific Revolution” in 1949; Steven Shapin opened a well-known 1996 book by denying there was any such thing — and then explaining why we talk about it anyway. The point of the debate is real: alchemy, theology and biblical chronology occupied Newton at least as much as optics did, and change was slower and messier than the word revolution suggests. Something decisive nevertheless happened by 1700, namely the settled expectation that claims about nature must be tested publicly and expressed mathematically where possible.

Section 4The Enlightenment: Reason Goes Public

From Newton’s method to society’s laws

The core Enlightenment wager was an analogy: if a few simple laws explain the heavens, then reasoned inquiry can find the laws of politics, economics, education and morality. Locke supplied the psychological half. His Essay Concerning Human Understanding (1690) denied innate ideas and described the mind at birth as blank paper written on by experience. If character comes from environment, then schools, laws, prisons and religions make people what they are — and can be redesigned. Reform became thinkable in a way it had not been when human nature was fixed by original sin.

Immanuel Kant gave the movement its slogan in 1784: enlightenment is humanity’s emergence from self-imposed immaturity, and its motto is sapere aude — dare to know. Note “self-imposed.” Kant blamed laziness and cowardice as much as tyranny, and he distinguished the private use of reason, where an official must do his job, from the public use, where a scholar addressing the reading world must be entirely free.

Skepticism cut both ways. Pierre Bayle’s Historical and Critical Dictionary (1697) modeled the corrosive footnote, showing that atheists might be virtuous and that most persecution rested on bad history. David Hume pushed further, arguing that causation is a habit of expectation rather than something we observe, and that no report of a miracle can outweigh uniform experience. A movement that began by trusting reason ended by interrogating reason’s own limits — which is precisely why Kant felt obliged to write the Critique of Pure Reason (1781).

The great texts and what they argued

Montesquieu, a Bordeaux magistrate, published The Spirit of the Laws in 1748 after two decades of comparative research. Laws, he argued, are not arbitrary; they arise from climate, religion, commerce and custom, and each form of government has an animating principle — virtue in a republic, honor in a monarchy, fear in a despotism. His prescription, drawn from an idealized reading of England, was the separation of legislative, executive and judicial powers so that, in his phrase, power checks power. American constitution-writers cited him more often than any other modern author.

Voltaire was the movement’s publicist and its conscience. After exile in England he praised its religious pluralism and its Newtonianism in the Letters on the English (1733), lampooned facile optimism in Candide (1759) after the Lisbon earthquake, and in 1762 took up the case of Jean Calas, a Toulouse Protestant broken on the wheel for a murder he did not commit. Three years of pamphleteering got the verdict annulled. That campaign, more than any treatise, showed what a writer with a public could do to a judicial system.

The Encyclopédie edited by Denis Diderot and Jean le Rond d’Alembert (28 volumes, 1751–1772) was the movement’s engine. It described stocking-frames and glassworks in exact detail, dignifying craft knowledge, and buried heterodoxy in cross-references — the article on cannibals sent readers to “Eucharist,” “Communion” and “Altar,” leaving them to draw the conclusion. Suppressed twice, it still sold thousands of sets. Rousseau, the movement’s great dissenter, denied that arts and sciences improved morals, argued in the Discourse on Inequality (1755) that property founded oppression, and in The Social Contract (1762) grounded legitimacy in the general will — a formula that has been read as democratic and as authoritarian ever since. Cesare Beccaria’s On Crimes and Punishments (1764) argued that certainty of punishment deters better than severity, and demanded the end of torture and the death penalty; Adam Smith’s Wealth of Nations (1776) explained how self-interested exchange, division of labour and open markets generate general prosperity — while warning that merchants seldom meet without conspiring against the public.

Salons, coffeehouses and the book trade

Ideas needed carriers. The public sphere — Jürgen Habermas’s term for a space between household and state where private people reason together about common affairs — took physical form in London coffeehouses (roughly 550 by 1740, each a penny university), in Masonic lodges, in provincial academies and reading clubs, and above all in the Parisian salon. Madame Geoffrin fed the encyclopedists on Mondays and Wednesdays; Julie de Lespinasse and Suzanne Necker managed conversation with a firm hand. Shut out of universities and public office almost everywhere, women nonetheless controlled introductions as salonnières, enforced the rules of civil argument and effectively curated who was heard.

Censorship shaped the trade rather than stopping it. French books carried false imprints reading Amsterdam or London; publishers in Neuchâtel and the Dutch Republic supplied the market; smugglers carried bales over the Jura. Robert Darnton’s research on those networks shows that the best sellers of the illegal trade were often not the polished treatises but scandal sheets, pornographic satires of the court and cheap philosophical pamphlets — which may have done more to corrode royal prestige than Montesquieu ever did.

Historians now stress the plural. There was a moderate Enlightenment that sought reform within monarchy and Christianity, and, in Jonathan Israel’s influential account, a radical Enlightenment descending from Spinoza that was materialist, democratic and hostile to revealed religion. There were distinct national flavours: a Scottish Enlightenment of Hume, Smith and Adam Ferguson centred on universities; a German Aufklärung respectful of the state and of Lutheran piety; a Jewish Haskalah around Moses Mendelssohn; a Catholic Enlightenment in Naples and Milan. Most philosophes were deists or heterodox believers, not atheists — and the same century produced Methodism, Pietism and Hasidism, revivals of feeling that were not simply reason’s enemies but its contemporaries.

Section 5Reason in Power: Reform, Empire and Contradiction

Enlightened absolutism, tested

Enlightened absolutism describes rulers who adopted the philosophes’ vocabulary — utility, tolerance, codified law, rational administration — without surrendering an ounce of sovereignty. Frederick II of Prussia (r. 1740–1786) called himself the first servant of the state, restricted judicial torture on his accession in 1740 and abolished it outright in 1754, allowed wide religious latitude, hosted Voltaire until they quarrelled bitterly, and ordered the legal codification that became the Prussian General Code of 1794. He also seized Silesia in 1740 in a naked war of aggression, tightened the Junkers’ grip on serfs and pressed hardest for the first partition of Poland in 1772, taking the smallest share by area but the one that mattered — the land bridge joining Brandenburg to East Prussia.

Catherine II of Russia (r. 1762–1796) corresponded with Voltaire and Diderot, bought Diderot’s library and left him its keeper with a salary, and in 1767 convened a Legislative Commission for which she wrote a Nakaz or Instruction lifted substantially from Montesquieu and Beccaria. The commission produced no code. After Pugachev’s massive Cossack and peasant revolt of 1773–1775 she reversed course, reorganized provincial government to strengthen noble control, and issued the Charter to the Nobility (1785) confirming their privileges. Serfdom expanded into newly conquered Ukraine. Rhetoric and reality had parted company.

Joseph II of Austria (sole ruler 1780–1790) was the genuine radical, and his failure is the most instructive. His Patent of Toleration (1781) granted Lutherans, Calvinists and Orthodox private worship and civil rights; the Edict of Tolerance for Jews (1782) opened trades and schools while pressing assimilation; he abolished personal serfdom in 1781 and, in his criminal code of 1787, the death penalty for almost all civil offences — judicial torture had already gone in 1776, under his mother Maria Theresa. He dissolved hundreds of contemplative monasteries and redirected their wealth to parishes and hospitals, including the great Vienna General Hospital. He also imposed German on Hungary, alienated the Church, the nobles and many peasants at once, and on his deathbed most of it was being repealed. Reform by decree, without consent, was brittle.

Evidence at the bedside

The century’s most defensible achievements were medical and demographic. John Graunt’s Natural and Political Observations on the London Bills of Mortality (1662) had already invented population statistics by treating death registers as data. James Lind ran what is usually called the first controlled clinical trial aboard HMS Salisbury in 1747, dividing twelve scurvy patients into six pairs and giving each pair a different remedy; the two men on oranges and lemons recovered, and his Treatise on the Scurvy (1753) followed — though the Royal Navy took four decades to act, and Lind himself hedged about the cause.

Smallpox drove the biggest change. Variolation — deliberately infecting a person with material from a mild case — was long practised in Africa, Anatolia, India and China. Lady Mary Wortley Montagu observed it in Istanbul, had her son inoculated in 1718 and her daughter in London in 1721, and pushed it into elite English practice. In Boston, where the enslaved African Onesimus had years earlier described the West African practice to Cotton Mather, the epidemic of 1721 prompted the physician Zabdiel Boylston to inoculate some 240 people; comparative death rates — roughly two percent among the inoculated against fourteen percent among the naturally infected — were among the first published epidemiological statistics in America. In 1796 Edward Jenner tested the folk observation that dairymaids who caught cowpox did not take smallpox, inoculating eight-year-old James Phipps with cowpox and then challenging him with smallpox. Vaccination was safer than variolation, and it spread across Europe within a decade.

These were Enlightenment achievements in method, not only in outcome: count the cases, compare the groups, publish the numbers, let strangers check them. That habit — not any particular remedy — is what modern clinical practice inherited from the eighteenth century.

The contradiction at the center

The same decades that produced declarations of natural rights saw the Atlantic slave trade reach its peak, with more Africans forcibly transported in the eighteenth century than in the sixteenth and seventeenth combined. Enlightenment writers built the intellectual case against it: Montesquieu’s savage irony in The Spirit of the Laws, the Abbé Raynal and Diderot’s History of the Two Indies (1770 onward), Condorcet’s Reflections on Negro Slavery (1781), Adam Smith’s argument that slave labour was economically inefficient. Organized abolition followed — Quaker-led petitioning, the Somerset ruling of 1772 that no master could forcibly remove a slave from England, the London Society for Effecting the Abolition of the Slave Trade (1787), the Société des Amis des Noirs (1788), and above all the testimony of formerly enslaved authors such as Olaudah Equiano, whose 1789 narrative went through nine editions in his lifetime.

But the same intellectual toolkit produced racial classification. Linnaeus sorted humans into varieties with temperamental traits attached; Blumenbach’s craniology, begun in 1775, coined “Caucasian” in its 1795 edition; Hume appended a footnote asserting the inferiority of Africans, and Kant lectured on race in terms no reader can defend today. A philosophy that grounded rights in a universal human nature also supplied the pseudo-scientific machinery for denying that some humans possessed it. Historians such as Sankar Muthu emphasize a genuine anti-imperial strand in Diderot, Kant and Herder; others stress how thin it was against the century’s racial thinking. The honest reading holds both.

Women’s position is the parallel case. Rousseau’s Emile prescribed for Sophie an education entirely oriented to pleasing men — from the author of a book on liberty. Yet the reading public he helped create included women in growing numbers, and the reply came quickly: Olympe de Gouges’s Declaration of the Rights of Woman (1791) and Mary Wollstonecraft’s Vindication of the Rights of Woman (1792), which argued that women appear frivolous because they are educated to be so, and demanded rational schooling as a matter of justice and of public utility. That argument, and the revolutions it collided with, carry directly into the next chapter.

Words worth knowing