Reason's Age

The change that saved the Western mind from its own certainties had, improbably, begun with a machine for making certainty cheaper. Around 1450, in a German workshop, Johannes Gutenberg combined movable metal type, oil-based ink, and the wine-press into a device that could stamp out identical pages by the hundred, and in doing so he did to knowledge what the printing of money does to coin: he made it flow. Within decades, books that had cost a scribe a year now cost a printer an afternoon, and ideas that the old order had controlled by controlling the few precious copies were suddenly everywhere, uncontainable, cheap enough for an artisan to own. The single most effective tool for suppressing knowledge had always been the scarcity of the copy. Gutenberg destroyed that scarcity, and the powers that had rested on it never fully recovered.

Onto this new and rushing river of print came a generation of minds who did something genuinely new in the world, or rather, who did openly and as a method what the hidden stream had done in secret: they decided to check. To look for themselves, to measure, to test the inherited authorities against the actual behavior of the actual world, and to believe the world over the authority when the two disagreed. Copernicus moved the Earth from the center of the cosmos and set it spinning around the Sun. Galileo turned his telescope on the heavens and saw mountains on the Moon and moons around Jupiter, facts that no ancient book had known, and for insisting on them was tried by the Inquisition and made to recant on his knees, a reminder that the old order did not surrender the right to define reality without a fight. Vesalius cut open the human body and drew what was actually there rather than what Galen had said would be. And at the century's end, Isaac Newton, the secret alchemist of our earlier chapter, gathered the falling apple and the wheeling Moon into a single law and showed that the same mathematics governs the heavens and the earth, the very "as above, so below" of the Hermetic tradition, now proven with calculus and made the foundation of a new physics.

This was the Scientific Revolution, and it is worth seeing clearly what it was, because it is the hinge of the modern world. It was not the discovery of this or that fact. It was the discovery of a method, a machine for generating reliable knowledge that did not depend on the authority, the holiness, or the sincerity of anyone at all, only on whether a claim survived being tested against nature and against other testers. It was, in the deepest sense, the serpent's promise institutionalized: you may know for yourself, you need not wait to be told. And it did not stay in the laboratory. The same daring turned onto human affairs became the Enlightenment, the audacious proposal that society itself, government, law, rights, could be examined by reason and remade, that authority must justify itself before the individual rather than the other way around, that there were truths a king could not overrule and a church could not forbid. The idea of universal human rights, of government by the consent of the governed, of the free and testing individual mind, was forged in this age, and it would within two centuries topple thrones on both sides of the Atlantic.

It is worth naming what that toppling looked like, because we still live inside its results. From the coffee-houses and the salons came a chorus of arguments that authority must answer to reason: John Locke held that a government exists only by the consent of the governed and may rightly be replaced when it betrays that trust; Montesquieu proposed splitting power into balancing parts so that no branch could tyrannize; Rousseau made the people themselves the only legitimate sovereign. In 1776 a set of English colonies declared it self-evident that all men are created equal and endowed with rights no king may cancel, and made the claim stick; in 1789 the French rose against a thousand years of monarchy in the name of liberty, equality, and fraternity, and though their revolution soon devoured its own children in terror, the idea outlived the guillotine. For the first time since the god-kings of Part V, large numbers of ordinary people asserted that legitimacy flows upward from the governed and not downward from heaven. The principle was, at first, radically incomplete in practice, proclaimed by societies that still held slaves and silenced women, and the long closing of that gap between the promise and the practice is much of the story of the centuries still to come. But the measure had been set, and every later movement for freedom would hold the world to it.

We should note, in fairness and in honesty, two things about this triumph. The first is that it was not the possession of Europe alone by any right of nature; China had printed books six centuries earlier, and had sent, in Zheng He, treasure fleets of hundreds of ships across the Indian Ocean decades before Columbus, only to burn the fleets and turn inward by imperial decree, a reminder that openness is a choice a civilization can make or unmake. The second is that the new method, for all its power, would prove no more immune than the old order to the temptation we have tracked all along. Reason, too, would learn to build its own orthodoxies and burn its own heretics, and the same age that freed inquiry also invented new and more efficient engines of conquest, and dressed some very old cruelties in the confident language of science. The light was real. It also cast a shadow, and the shadow lengthens through the next two chapters. But something irreversible had happened. Humanity had built a tool for knowing that worked, that compounded, that crossed borders and generations, and once it was loose in the world, the pace of everything began to change.

By the end of the eighteenth century the change was becoming visible to the eye, in smoke.