The season of fiction is now over.


Fact is superior to reasoning.


Historians agree that the democratic revolution grew out of the Enlightenment, but if you ask what caused the Enlightenment, you are likely to be presented with a list of philosophers—Bacon, Locke, Hume, Berkeley, Descartes, Voltaire, and Diderot among them—who for some reason suddenly began singing in unison on behalf of reason and rights. Unless this was a coincidence, something must have happened—something of lasting consequence, capable of shifting the balance away from traditional beliefs and toward the enlightenment values of inquiry, invention, and improvement.

Science fits the bill. Science discovered new facts that were interesting in themselves but also rewarding—literally so, since they proved effective in curing disease, reducing toil, and making money. Science worked in new ways, rewarding merit rather than social station, challenging aristocratic traditions with a force mustered by no prior system of thought, and underscoring the liberal claim that humans have natural rights. Other influences were at work as well, but the Enlightenment without science would have been a steamship without steam.

The Enlightenment is customarily dated from England’s Glorious Revolution of 1688, but a more appropriate date would be one year earlier, with the publication in 1687 of Isaac Newton’s Principia, which was taken up by thinkers across Europe almost overnight. “Newton rose at once to the highest pinnacle of glory,” wrote Thomas Thomson in his history of the Royal Society, and “has stood ever since in the front of the philosophic world.” David Hume declared Newton to be “the greatest and rarest genius that ever rose for the ornament and instruction of the species.” Alexander Pope celebrated him in a poem: “God said ‘Let Newton be,’ and all was light.” The French philosopher Jean d’Alembert observed in the mid–1700s that Newton’s account of gravitation was “so generally accepted, that people were beginning to dispute their author the honor of having discovered it.” Newtonian precepts were soon being tried out, with mixed results, on everything from medicine and ethics to government. “We are all his disciples now,” said Voltaire in 1776.

Newton was obviously a great scientist, but he was not only a scientist. He was also a dedicated radical Whig—what today would be called a classical liberal—who stood up for liberty in the face of direct threats from the highest authorities. Reclusive, paranoid, and peculiar even by the standards of his fellow dons, Newton was nobody’s idea of a professional politician, yet he enjoyed enough political success to be described today as “one of the architects of our civil liberties.” His were politically tumultuous times; to appreciate just how tumultuous calls for a bit of background.

When the Principia was published, England had been suffering through a bloody half century that saw seven years of civil war; the beheading of a reigning monarch, Charles I, in 1649; a turbulent interregnum during which the monarchy was restored; and the Glorious Revolution itself, in which King James II was deposed. Pressing for further change were the gentry and other self-made traders, merchants, and artisans, who by 1628 comprised the majority of the House of Commons and controlled triple the wealth of their social superiors in the House of Lords. The ship of state seemed near to capsizing.

An adept monarch might have been able to keep it aright for a while, and the Tudor queen Elizabeth I was fondly remembered for having managed to do just that, from her coronation in 1558 until her peaceful death on March 24, 1603, shortly before her seventieth birthday. But the crown thereafter devolved to the Stuart regents James I (who ruled from 1603 until 1625) and his son Charles I (crowned in 1625 and beheaded in 1649). Both were the sort of leaders who, unable to master the intricacies of the job, take refuge in an unblinking adherence to unwavering precepts of religious and secular faith. (The historian G. M. Trevelyan says of James that “he was perpetually unbuttoning the stores of his royal wisdom for the benefit of his subjects, and as there was none who could venture to answer him to his face, he supposed them all out-argued.”) When such a ruler gets into trouble he is less apt to question his beliefs than to repeat them with heightened vehemence, as if bluster were a magical spell capable of revitalizing his ebbing power. The worse things get, the less he listens and the more he talks.

James and Charles shared an arrogant disdain for Parliament as well as a belief in the divine right of kings, James informing Parliament during a two-hour harangue in March 1610 that “kings exercise a manner of resemblance of divine power on earth.” These traits angered many British subjects, but when Charles finally heard the waterfall’s roar of imminent disaster he steered straight for it, assembling an army and declaring war on Parliament. Four years of conflict ended in his defeat, trial, and condemnation, but he remained resolute. Standing on the scaffold on January 30, 1649, Charles said of his subjects, “I must tell you that their liberty and freedom consist…not for having share in government, sirs; that is nothing pertaining to them; a subject and a sovereign are clear different things.”

Unpopular though Charles may have been, his execution aroused revulsion among those who associated monarchy with the rule of law (an Aristotelian precept still taught at all the universities), and a decade later his eldest son was invited back from exile in France to be crowned King Charles II, in 1661. But hopes for the Restoration were disappointed, Charles II signing a secret treaty with the king of France promising to publicly declare his Catholic faith in return for a bribe and such French troops as might be required to put down any resultant rebellion, then denying to Parliament that any such treaty existed. His brother James II, crowned in 1685, pursued a similar course, further alarming his Protestant subjects by ordering Catholics appointed to high posts at the universities of Oxford and Cambridge. He seems to have underestimated the universities’ prestige; as Thomas Babington Macaulay writes in his History of England:

James II ordered Cambridge to name as Master of Arts a Benedictine monk who refused to take the oath of obedience required by parliamentary law. University officials, objecting that they could not legally obey the edict, dispatched eight distinguished professors to plead their case before an ecclesiastical commission at Westminster in April 1687. Newton was among them. “He was the steady friend of civil liberty and of the Protestant religion,” Macaulay writes of Newton, “although his habits by no means fitted him for the conflicts of active life. He therefore stood modestly silent among the delegates, and left to men more versed in practical business the task of pleading the cause of his beloved University.” It hardly mattered. The chief inquisitor was Sir George Jeffreys—a manically abusive judge notorious for unleashing torrents of invective on the trembling miscreants brought before his bench—and he dismissed the Cambridge delegation without a hearing. “Go your way and sin no more,” he thundered, “lest a worse thing happen to you.” Oxford fared little better. When Jeffreys was unable to expel the elected president of Magdalen College and replace him with a bishop of the king’s choosing, James himself turned up with a full glittering retinue (having paused along the way at Portsmouth to soothe scrofula victims with “the king’s touch”) to personally intimidate the dons. “Go home,” he roared, tossing aside a faculty petition without reading a word of it. “Get you gone. I am King. I will be obeyed…. Let those who refuse look to it. They shall feel the whole weight of my hand. They shall know what it is to incur the displeasure of their Sovereign.”

The king prevailed, dispatching troops with loaded carbines to install the bishop and begin the process of transforming Magdalen into a Catholic seminary, but his affronts became the fodder of revolutionary chatter in coffeehouses and newspapers across the land. The birth of a male heir to the previously childless monarch in 1688 aroused fears that yet another generation of Stuart rulers would continue turning back the clock. Within a year James had been deposed, driven into exile by an army that sailed over from Holland under the command of William of Orange at the invitation of seven English peers. (Related by marriage to the English royal family, William had made himself popular with the British by his skillful conduct of Dutch defenses against the French.) No sooner were William III and Queen Mary II enthroned than Parliament, with Newton its representative from Cambridge, enacted the Bill of Rights of 1689. It forbade British monarchs from independently raising money or creating armies in times of peace, infringing on freedom of speech, interfering with due process of law, or suspending acts of Parliament. England had become a constitutional republic, albeit one without a written constitution. Viewed in terms of a dialectic between Whigs (believers in science and material progress, apt to have supported Parliament in the civil war) and Tories (mostly monarchists and royalists, more concerned with stability than with social or scientific innovations), the Whigs had prevailed.

It was in these circumstances that Newton met John Locke, probably in the spring of 1689, the two forming a friendship that thrived until Locke’s death fifteen years later. Both were radical Whigs and devotees of science, but they were personally quite distinct. Locke had many friends, the prickly Newton few. Locke was voluble, Newton more apt to reserve his thoughts for the printed page. Newton was the most famous Englishman alive; Locke’s celebrity was limited to intellectual circles until publication of three long-suppressed works—his Essay Concerning Human Understanding, Treatises of Government, and Letters on Toleration, arguing that governments are obliged by a “social contract” to protect “natural rights,” including right to “life, liberty, and the ownership of property”—made him a luminary. Locke was eager to know not only Newton the preeminent scientist, whose Principia had recently dawned like a second sun, but Newton the political activist, who in addition to joining the Cambridge delegation mustered against the intrusions of James II had recently denounced the king’s mandates as violations of common law. In that document Newton urged his academic colleagues to “be courageous therefore and steady to the laws,” adding that “an honest courage in these matters will secure all, having law on our sides” and reporting to his Cambridge colleagues that “fidelity & allegiance sworn to the King, is only such a fidelity & obedience as is due to him by the law of the land. For were that faith and allegiance more than what the law requires, we should swear ourselves slaves & the King absolute; whereas by the law we are free men.”

Locke, like Newton, was a man of modest origins whose early career had been deceptively quiet. Born in a Somerset village on August 29, 1632, to middle-class parents of evident moral standing (his father was sensitive enough to apologize to the adult Locke for once having struck him when he was a child, and Locke described his mother, reputedly a great beauty, as unfailingly loving), Locke was admitted to Christ Church, Oxford, as a scholarship student in 1652. He got off to an unpromising start, complaining that he was not cut out to be a scholar—due most likely to the fact that, as the encyclopedist Jean LeClerc noted, “the only philosophy then known at Oxford was the peripatetic [that is, Aristotelian], perplexed with obscure terms and useless questions.” Locke was rescued by his discovery of science, which arrived at Oxford in the person of John Wilkins, a burly, unbookish man who formed a club for the purpose of conducting experiments. Under Wilkins’ tutelage, Locke finally found his footing. He learned astronomy from a royalist, Seth Ward, and geometry from a Whig, John Wallis, who, moonlighting as a cryptographer, decoded intercepted Royalist messages for the Parliamentarians in the English Civil War. Eventually settling on medicine, Locke worked with Dr. Thomas Sydenham, called “the English Hippocrates,” a founder of epidemiology and enemy of dogma who taught that physicians should trust only “the faithful product of observation,” supported by “the only true teacher, experience.” Locke pursued science all the rest of his days. He kept meteorological records, studied the atmospheric effects of the great London fire of 1666 (popularly regarded as the satanic apocalypse predicted in the Book of Revelations), observed Jupiter and Saturn from the Paris Observatory, and counted among his friends the Danish astronomer Olaus Rømer, the Irish astronomer William Molyneux (whose pamphlet demanding equal rights for Irish citizens under English rule was burned on order of Parliament), and Robert Boyle, Britain’s greatest chemist.

Locke’s scientific and medical studies pleased him sufficiently that he remained at Oxford for seventeen years. He never obtained a medical degree, but at one point supervised an operation to remove a suppurating liver cyst that was troubling Lord Ashley, later the first Earl of Shaftesbury, a radical Whig depicted by the royalist poet John Dryden as a Satan whose goal it was

That Kingly power, thus ebbing out, might be

Drawn to the dregs of a Democracy.

Against all odds the procedure actually cured Shaftesbury, who became Locke’s patron. Thus supported, Locke wrote a number of liberal political essays that he prudently kept to himself. One of them, the Essay Concerning Toleration, is a classic statement of the case for religious freedom, and a masterpiece of clearheaded reasoning and soaring rhetoric: “Now, I appeal to the consciences of those that persecute, torment, destroy, and kill other men upon pretence of religion, whether they do it out of friendship and kindness towards them or no?” When Shaftesbury was named lord protector of Carolina, Locke wrote and published the “Fundamental Constitution of Carolina” of 1670, providing that “no person whatsoever shall disturb, molest, or persecute another for his speculative opinions in religion or his way of worship.” Its liberalism made Carolina a magnet for refugees fleeing religious persecution.

As one of Shaftesbury’s pilot fish, Locke rose high when the great man became the most powerful figure in the court of Charles II, and descended to the depths when, by 1682, Shaftesbury’s growing opposition to the king’s high-handed fiats put his life in danger. Accused of plotting against the crown along with Lord William Russell, Algernon Sidney, and the Lords Essex and Salisbury—all of whom were soon imprisoned in the Tower of London, and soon thereafter dead—Shaftesbury fled to the Netherlands, where he too promptly died, just two years later. The relatively inconspicuous Locke might have survived in England, but he had by this time drafted his Two Treatises of Government, a seditious manuscript that endorsed human rights as natural. Fearing that he was being spied upon (rightly so, the Crown having dispatched lip-readers to transcribe his private conversations in the university dining hall), Locke in 1683 followed his patron’s example and decamped for Holland.

The Dutch were the architects and beneficiaries of what would be known as their Golden Age (1609–1713), an era during much of which Holland was pretty nearly the freest—and per capita the wealthiest and most creative—nation in the world. The Dutch dominated world maritime trade, owing in large measure to the fact that their ships, built to suit the practical needs of merchants rather than the vanity of regents, were broad-beamed, commodious, and easily maintained. (The other side of the coin was that Dutch warships tended to be converted merchant vessels, a liability that contributed to their defeat by British ships of the line in the three Anglo-Dutch wars of 1652–1674.) Their maritime empire stretched from Japan, where they enjoyed a trade monopoly that would last until 1853, to New Amsterdam, founded in America in 1625 as a private corporation and granted self-government in 1652, thereafter to become the West’s most commercial city. Their robust, republican, and relatively egalitarian society stood up to the mighty military forces of two retrograde regents, Philip II of Spain and Louis XIV of France. They counted among their philosophers immigrant freedom-seekers like Descartes; the liberal skeptic Pierre Bayle, whose Historical and Critical Dictionary of 1697 would find its way onto Thomas Jefferson’s list of the one hundred books vital to establishing the American Library of Congress; and now John Locke.

The greatest of Holland’s indigenous thinkers was Benedict de Spinoza, who like many philosophers professed the virtues of self-sufficiency and tranquil contemplation, but unlike most of them actually lived that way. A lens-grinder by trade, Spinoza contributed to the development of the microscope (and died of glass dust in his lungs), lived modestly (pipe-smoking was his only vice), worked assiduously (a friend said he once went three months without leaving the house), and shunned all honors, declining a professorship at the University of Heidelberg in 1673 “not in the hope of some better fortune, but from love of tranquility.” Recognizing science as “the only certain and reliable criterion of truth we possess,” Spinoza equated God with the universe and thus regarded scientific investigation of nature as doing God’s work—an outlook which at the time seemed so radical that Spinoza was excommunicated by his fellow Jews and narrowly survived an assassination attempt. (Seeing the gleam of the knife thrust at him by a stranger on a dark street, he turned aside and evaded it, keeping his slashed overcoat for the rest of his life as a kind of memento mori.) He was a liberal (“The purpose of the state is freedom”) and a democrat. “Democracy,” he wrote, “is of all forms of government the most natural and most consonant with individual liberty.” He regarded miracle-mongering theocrats as akin to illiberal politicians, since both enhanced their power by encouraging the irrational fears of the multitude:

For such efforts—and for denying human immortality and the existence of a personal god who wields supernatural powers and takes an interest in human affairs—Spinoza was called an atheist, notwithstanding his having composed a fourteen-part proof of the existence of God.

The Dutch innovated oil painting, mixing earthen pigments with cold-pressed linseed oil in technologically advanced shops like the Old Holland Oil Color Factory, established in 1644 and still in business today. They created new styles of painting as well, influenced in part by the use of optical devices such as the pinhole camera, the refracting or “Gali-lean” telescope, and lenses which could project an inverted image onto a blank canvas. One such projector is thought to have been developed by the naturalist and microscopist Antoni van Leeuwenhoek and employed by Johannes Vermeer, both of whom worked in Delft. Art historians today debate whether Vermeer and other painters were in some sense cheating if indeed they used optical projection to sketch the outlines of their paintings, but it is perhaps more to the point to observe that the Dutch were quick to apply the results of scientific experimentation to the fine arts. Dutch paintings celebrated freedom, industriousness, and prosperity—as in Vermeer’s The Lacemaker, Jacob van Ruisdael’s View of Haarlem with Bleaching Grounds, and Rembrandt’s The Sampling Officials of the Clothmakers’ Guild, Amsterdam. In a break from the spiritual themes of the past, painters memorialized everyday scenes of housework, shopping, farming (the coming agricultural revolution in England would spring largely from experimental innovations developed by the Dutch), and technology (especially maritime technology; Dutch painters depicted sailing ships so reliably that maritime archeologists today use their paintings to re-create the lost rigging of recovered vessels). Science was celebrated in canvases such as Rembrandt’s The Anatomy Lecture of Dr. Nicolaes Tulp and Vermeer’s Astronomer, who studies a celestial globe while bathed in light streaming through a window so radiantly as to suggest an intellectual awakening. The beauty of these canvases indicated that scientific inquiry, technological advancement, and free-market commerce could be carried out in harmony with nature, an outlook later jeered at by romantics who accused science of draining the mystery from existence (Wordsworth’s “We murder to dissect”) and technology of dehumanizing humankind (William Blake’s “dark satanic mills”). Such paintings became so popular that Dutch painters developed “wet-on-wet” overlaying techniques to complete their canvases faster and meet the rising demand, while their agents invented the practice of selling art at auction to maximize profits. As one modern historian puts it:

Here were products of a major European civilization—the very best products of that civilization—created by burghers for burghers. The existence of these works and their quality proved that no social elite was required for the creation of great art. The aristocracy was superfluous, the church irrelevant. Bourgeois artists attuned to the basic conditions of life around them, trusting their sensibilities and powers of observation alone, were capable of capturing the ultimate meaning of their culture.

Following the death of Rembrandt in 1669, the artistic inclinations of the Netherlands increasingly were expressed through natural history illustrations. Some of these works took the form of tropical landscape paintings, a genre invented by the Dutch that combined geographical and botanical depictions of Brazil, North Africa, and the East Indies. Many appeared in sumptuous books like Maria Sibylla Merian’s Metamorphosis Insectorum Surinamensium of 1705, a study of the insects of the Dutch colony Surinam; Hendrik Adriaan van Reede tot Drakenstein’s Hortus Malabaricus, a twelve-volume botanical work containing over six hundred plates; George Rumpf’s monumental book on Moluccan shells, The Ambionese Curiosity Cabinet; Simon de Vries’s two-thousand-page Great Cabinet of Curiosities, which ranged from the wampum of American Indians to the marital customs of the Laplanders; and the Hortus Cliffortianus of Carl Linnaeus, the “father of taxonomy,” who was born in Sweden but developed the basis of his system for classifying plants while studying at the universities of Harderwijk and Leiden. Dutch collectors accumulated such vast inventories of the world’s biological and anthropological wonders that many of today’s methods of scientific classification had to be developed just to keep track of them.

Dutch society, like Dutch art, evoked a harmonious interplay between liberalism and science. As the historian Johathan I. Israel notes:

Visitors continually marveled at the prodigious extent of Dutch shipping and commerce, the technical sophistication of industry and finance, the beauty and orderliness, as well as the cleanliness, of the cities, the excellence of the orphanages and hospitals, the limited character of ecclesiastical power, the subordination of military to civilian authority, and the remarkable achievements of Dutch art, philosophy, and science…. Until the late seventeenth century many were appalled by the diversity of churches which the authorities permitted and the relative freedom with which religious and intellectual issues were discussed. Others disapproved of the excessive liberty, as it seemed to them, accorded to specific groups, especially women, servants, and Jews, who were invariably confined, in other European countries, to a lowlier, more restricted existence.

The Dutch were tolerant of such criticism; they were tolerant of just about everything.* They could afford to be. Having hit upon the magic triangle of science, technology, and liberal trade policies, they inhabited a seventeenth-century version of Tomorrowland, a state that demonstrated daily how a free, scientific world could work.

Locke thrived during his five years in the Netherlands, maturing into the accomplished, if still almost entirely unpublished, author who would become an architect of the Enlightenment and a preeminent exponent of science and liberalism. He quietly toured Dutch universities and studied local medical and technological improvements while conspiring with fellow Whig exiles to keep rebellion boiling back home in Britain. As a fugitive from justice—a warrant for his arrest and extradition having been issued in England—Locke was obliged to live in hiding, receiving his mail under assumed names and laboriously conducting his research from books hidden in secreted caches. Such a life is easy for no scholar, but Locke was accustomed to conflict—having grown up during the English Civil War, he recalled, “I no sooner perceived myself in the world but I found myself in a storm”—and the Dutch authorities were disinclined to betray him. William of Orange heeded the letter of the law in ordering enforcement of King James’ arrest orders—James was, after all, his father-in-law—but he did so with a wink and a nod, issuing fair warning before dispatching the police to search any of the private homes known to shelter Locke. In the preface to his Essay Concerning Human Understanding, Locke coolly refers to its having been completed while he was “in a retirement where an attendance on my health gave me leisure,” without mentioning that the principal threat to his health was that of his being dragooned back to the Tower of London and the execution block.

Locke read Newton’s Principia soon after its publication. Its mathematics were beyond him so he asked the great Dutch mathematician Christiaan Huygens for help. He had picked the right man. Huygens was a diplomat, lute player, creator of a thirty-one-tone music temperament, inventor of a cycloidal pendulum employed in wristwatches and marine chronometers, a telescope builder who discovered a satellite of Saturn, and a talented physicist with ample experience in applying mathematics to the study of nature. It was Huygens who had first derived the law of centrifugal force for uniform circular motion, a step that incited Halley to hypothesize that gravitation obeys an inverse-square law of attraction and to ask Newton about it—which in turn led to Newton’s composing the Principia. Huygens took exception to some aspects of Newton’s theory, regarding it as “absurd” to imagine gravitational force somehow propagating itself across a vacuum of space, but he assured Locke that the work was mathematically trustworthy. Locke then devoted himself to absorbing Newton’s work, and emerged understanding better than most how and why it changed the world.

It was one thing to speculate, as many scientists had, that nature was built on a logical, mathematically intelligible basis, but Newton had shown nothing less than that the behavior of all objects influenced by gravity—from thrown stones on earth to the orbits of the moon and planets—could be predicted by means of mathematical formulas. Locke was so impressed that in the “Epistle to the Reader” prefacing his Essay Concerning Human Understanding, he referred to Newton’s “never enough to be admired book” as constituting “the greatest exercise and improvement of human understanding” yet accomplished. Locke added modestly of his own work:

In an age that produces such masters as the great Huygenius [i.e., Huygens] and the incomparable Mr. Newton, with some others of that strain, it is ambition enough to be employed as an under-laborer in clearing the ground a little, and removing some of the rubbish that lies in the way to knowledge.