The Industrial Revolution is the inflection point of economic history. During all the millennia before that revolution, incomes were static and humans were poor—often hungry, inadequately clothed, ill-housed. But somehow, in the two-and-a-half centuries since humanity learned to mass produce, a large number of ordinary people have acquired more material comfort than even the wealthiest magnates of the pre-industrial era. A modern Wal-Mart would have been a place of incalculable riches to Charlemagne.
The industrial revolution’s importance as the key economic watershed makes it big game among economic historians. Some of the biggest names in the field—Arnold Toynbee, T. S. Ashton, Hobsbawm, Landes—have tried to explain its mysteries. Now Joel Mokyr, a distinguished economic historian, has published a sprawling exploration of England’s early industrial age. Mokyr is best known for The Lever of Riches, a magisterial history of technological progress, and his erudition, earned over more than three decades of studying the Industrial Revolution, is everywhere evident in his important new book. As befits a scholar of human knowledge, Mokyr's overarching thesis is about the power of ideas. His grand idea is that the practical, avaricious inventors of the industrial revolution owed much to the academic, but worldly, philosophers of the Enlightenment.
The Enlightened Economy is a wide and deep chronicle of one hundred and fifty years of British economic history. Interested in eighteenth-century agriculture? Mokyr teaches us that “high productivity in British agriculture was maintained by” among many other things, “the famous Norfolk rotation in which clover and turnips were rotated with barley and wheat.” Did you want to know how people got healthier before doctors really understood disease? Mokyr emphasizes the improvements around medical interventions: the smallpox vaccine “spread like wildfire through Europe and beyond,” in part because “by 1806, the Royal College of Surgeons had data for over 164,000 vaccinations and could readily assess its efficacy.” And what explains the three-fold increase in English population between 1750 and 1850? Mokyr reports that fertility control within marriage was largely irrelevant and that “it attests to this age’s embarrassment with [condoms] that they were called ‘French letters’ in England and ‘la capote anglaise’ in France.” Instead, “the decline in the age at first marriage of women during the eighteenth century was the driving force behind the rise in British fertility rates.”
The Industrial Revolution was a major turning point for human prosperity, but Great Britain did not get rich overnight. Throughout the century, per capita national income grew at half a percent per year or less. This was slow progress, and in this sense utterly unlike the current economic explosion in China and India, where growth rates routinely top 5 percent per annum. Not until the middle of the nineteenth century did per capita growth rates creep up to 2 percent, which have been roughly the norm in the United States and the United Kingdom in recent decades. Over the entire period of Mokyr’s study, men’s wages, corrected for inflation, rose by only 55 percent. We may conclude, then, that the Industrial Revolution was so important not because the level of prosperity surged, but because the growth rate of income rose. Over enough time, a somewhat higher growth rate means a vastly higher standard of living.
No serious scholar who approaches the Industrial Revolution can avoid addressing the question of why it happened when and where it did. Why not medieval China? Why not France? In 2007, Gregory Clark’s A Farewell to Alms received a great deal of attention by suggesting that natural selection produced Englishmen who were particularly endowed with personal virtues, such as literacy and thrift, that engendered the industrial revolution. Mokyr is somewhat skeptical about such an explanation, observing that “these Darwinian dynamics, however innovative and stimulating, have limited power.” Generations are too long. Natural selection operated in many places other than England. I suspect that for most of English history natural selection favored prowess with a pole-axe over the bourgeois virtues that made good industrialists.
It won’t make his book more popular, but Mokyr wisely refuses to offer any single explanation of why the Industrial Revolution happened in the eighteenth century and in England. He notes that Britain “as an island nation was more difficult to invade” and the country’s “large supply of coal and iron in reasonable vicinity of one another,” but then he cautions that “theory and evidence plead against too ready an acceptance of the belief that geography was destiny.” He disagrees with the view that international trade can “take credit for the Industrial revolution,” but he later concludes that “the openness of the economy was thus an important part of the story.”
Mokyr belongs to a group of economists who emphasize the importance of political institutions that encourage investment by protecting private property, but he again shows restraint: “Effective property rights are rightly considered crucial for economic development, but they were not the entire story.” He also emphasizes the human capital—the skills and talents—of eighteenth-century Britain, which were created, he says, as much by practical experience and commercial culture as through formal education: “The middle classes in eighteenth-century Britain were full of practical men of enterprise, attuned to the markets, networked and connected, joined in a common ambition to make money and willing to work for it.” And Mokyr emphasizes the technical skills: clock-making, mining, shipbuilding.
While the reader craves a simple explanation, there is none to be had. The entire question of why the industrial revolution started in England will never be definitively answered. The event was sui generis—a one-off, as the English say—a bolt of lightning; and there are a myriad of possible explanations for it. Some of those theories can be rejected, but many of them remain reasonable. The scholarly, if unsatisfying, path is to understand the details of the Industrial Revolution and then judiciously to suggest, as Mokyr does, which forces may have played a major role, and which theories are pure balderdash.
But while Mokyr does not claim to have discovered the one true cause of the Industrial Revolution, there is a grand central message that unifies his book. It is that the industrial revolution owes a great deal to the Enlightenment. “What is new here,” he writes, “is not an argument that the Enlightenment changed history, for better and/or worse, but that its economic effects on the wealth-creating capabilities of the affected societies have been overlooked.” Mokyr has long emphasized the economic value of new ideas and he thus emphasizes that “Britain’s intellectual sphere had turned into a competitive market for ideas, in which logic and evidence were becoming more important and ‘authority’ as such was on the defensive.”
Mokyr’s emphasis on the market for ideas is surely right, for the Industrial Revolution was at its heart an intellectual explosion. It was a burst of ideas about how vast quantities of cloth could be made cheaply and how the power of steam could be harnessed. It was a connected stream of innovations by smart Britons who learned from one another in hubs such as Birmingham and London. But is it right to see the roots of this intellectual explosion in the Enlightenment? Mokyr is surely right that that the leaders of the Industrial Revolution were all practical men who were interested in knowledge, but must we credit the Enlightenment anytime someone pursues earthy insights in a methodical manner?
A tougher test of his hypothesis is whether there were clear links between the doers of the Industrial Revolution and the thinkers of the Enlightenment. In some cases, the link is obvious. James Watt apprenticed as an instrument-maker in London, but then spent much of his early adult life working at the University of Glasgow, a hotbed of the Scottish Enlightenment. I do not know if Watt learned anything from Adam Smith, who was there at the same time, but he certainly benefitted greatly from proximity to other academic luminaries such as Joseph Black and John Robison. Black not only influenced Watt’s understanding of latent heat, but also helped to finance Watt and connected him with John Roebuck, a student of Black’s who became Watt’s first large-scale investor. Watt and his steam engine were clearly children of the Scottish Enlightenment.
The role of the Enlightenment is a little murkier on the textile side of the Industrial Revolution. The intellectual path that led to the erstwhile wigmaker Richard Arkwright’s water-powered spinning frame—a seminal piece of textile machinery—goes back through the clockmaker John Kay to the reedmaker Thomas Highs to the carpenter John Wyatt to the crepe-pinking (don’t ask!) Huguenot Lewis Paul, who seems to have first come up with the idea of spinning with rollers in 1738. All of these men were inventive (Arkwright first made his money by coming up with a waterproof wig dye), but none of them had obvious associations with universities or learned societies or philosophies. What does the Enlightenment have to do with this inspired string of tinkerers?
Or so I wondered as I read Mokyr’s account. Then I did a little digging of my own, and discovered that he is right: the Enlightenment was important even to this seemingly un-intellectual chain of craftsmen. The father of Lewis Paul—the ur-inventor of roller-spinning—had been doctor to the third Earl of Shaftesbury, just as John Locke had been doctor to the first Earl of Shaftesbury. And the third Earl was a seminal figure of the Enlightenment, whose philosophical writings influenced Hume, Smith and Diderot. When Lewis Paul’s father died, the Earl become the inventor-to-be’s guardian. Paul’s financial backers would later be men of letters, such as Edward Cave and quite possibly Samuel Johnson himself. We may never know where Lewis Paul got his ideas, but he was certainly immersed in the intellectual turbulence of his age.
It is easy to envision the massive mills of Manchester and think that the Industrial Revolution was all about scale and machines. But there was more. At its core, this economic and technological revolution was created by connected groups of smart people who stole each others’ ideas and implemented them. I tend to think that the chain of interrelated insights that brought us industrialization could have happened in other countries and at other times, but there is every reason to think that the Enlightenment had readied England’s intellectual soil for industrial innovation. Not least because it persuades readers of the plausibility of such an unlikely and colorful causation, Mokyr’s book is a splendid achievement.
Edward Glaeser is the Glimp Professor of Economics at Harvard. He directs the Taubman Center for State and Local Government and the Rappaport Institute for Greater Boston.