This is a work of prodigious scholarship. It is, first, a description of economic change in Britain (note: not Great Britain; Ireland is largely excluded) that covers almost every angle one can think of—technology, trade, agriculture, transport, mining, finance and credit, coinage, health and medicine, population, consumerism, labor movement and productivity, capital accumulation, patents, gender and family relations, poor relief, firm and factory organization, social norms of exchange and trust, political and economic institutions, war costs, living standards, and inequality. Second, Joel Mokyr presents a thesis on the driving force behind these changes, and that is the power of a change in outlook and thinking that permeated the most active segments of society, namely the Enlightenment.

One can hardly quibble with the book as a description of the vast panoply of change in this period. Mokyr is our generation's leading expert on the Industrial Revolution, but this book is much more than another account of the Industrial Revolution. Rather, it is a sweeping picture of Britain that shows in exhaustive (and sometime exhausting) detail how many aspects of life changed dramatically in the century and a half after 1700. During this period, slavery went from accepted to banned; national debt and tax rates skyrocketed; Britain went from being a rocky steward of Ireland and Scotland to mistress of an empire that spanned the world; tea became the national beverage; population trebled; new cities erupted in size and social turmoil; strong monarchy gave way to parliamentary rule; and oh yes, output of coal, cotton, and iron rose by orders of magnitude, and wholly new inventions (steam power, railroads, iron construction, and gas lighting) appeared and came into wide use.

The changes were so many and boggling in their diversity and detail that it is easy to see why debates have raged over causal connections—did improved credit promote industrialization? Or was it shifts in labor and population? Or were those the result of industrial growth? Were factories critical or an organizational convenience? Did industry drive fashion and consumption or was industrialization demand-led? Did domestic industry arise because of imperialism or in spite of it?

To his credit, Mokyr does not attempt to sort out such matters—rather he gives all single- or primary-cause explanations of Britain's sea-change a respectful hearing but makes plain their inadequacy to account for the multitude of diverse changes he presents so well. He does so mainly through marshalling the historian's tools—summaries of key events and vignettes of important actors and their actions. Economists may be surprised that Mokyr, who made his name as one of the leading cliometricians, steers clear of any equations. Numerical data appears in only about a dozen tables (in a text of nearly 500 pages). Mokyr does summarize the latest economic research and debates on controversial issues, including accounts of the results of computable general equilibrium models, but the emphasis clearly is on exposition accessible to those more literate than numerate, and in that he succeeds with aplomb.

For example, he notes Robert Allen's argument that British industrialization resulted from choices made by British entrepreneurs facing unusually high wage costs and low costs of capital and energy. But Mokyr makes it plain that such factors, even if they may have been important in guiding investment in textile production, cannot account for the adoption of steam power in Cornwall (where coal was relatively expensive, and hence technical efforts focused on reducing the capital and fuel costs of engines), nor for the host of changes in other areas from soda-bleaching to gas lighting to road and carriage improvements to steel and ceramic production, where producing new materials that were higher in quality was the main goal. Indeed, Mokyr notes that only one-fifth of patents in this period appear to have had labor-saving as their main purpose. Moreover, he argues that the real productivity of British labor was already much higher than on the continent even before industrialization, due to better nutrition and improved agricultural methods, so that high real wages may simply have reflected higher output per worker, not a cost disadvantage to labor utilization that was absent elsewhere (pp. 270–71).

Mokyr is utterly convincing on two counts. First, the enormous array of major and minor changes in social and economic life in this period was so vast as to make it impossible to see them stemming from only one arena, whether it was relative wage costs, or trade, or imperialism, or any other single factor. Second, this period was one of such immense, paradoxical contradictions that contemporaries were often confused, seeing parts of what was happening though it was impossible to see it all. Thus we find rampant unbounded optimism for universal improvement alongside stark pessimism regarding the conditions of life in cities and for the working class. We find new industrial fortunes being made while much of southern England (and most of Ireland) remained mired in agrarian poverty. We find radical changes in some aspects of life and production and only minimal or incremental changes in others. I was struck in reading by the similarities between this period of British change and the current decades in India, where alongside the established agricultural and industrial sectors there has grown up, in part because it was at first unnoticed and unanticipated by the state, a booming software and international services industry that has fueled new cities, a new middle class, and immense private fortunes, while the majority of Indians remain largely untouched by these changes and stuck in some of the world's worst poverty. Britain in the early 1800s must have been as bewildering as India today.

What of Mokyr's thesis that all of this was fueled by the Enlightenment? In one sense the argument is well-supported, in that changes so widespread in behavior must have had roots in a broad change in outlook in society. Yet Mokyr recognizes that this just pushes explanation back from one big change (industrialization) to another (enlightenment), and he has no good explanation for why the Enlightenment took root when and where and as deeply as it did (pp. 487–88). Rather, he backs away and calls the Enlightenment just one cause for all these changes, along with favorable geography, prior growth of a middle class, and available human and natural resources. Moreover, he even suggests that its adoption in Europe may have been more a matter of contingency rather than an economic or historical necessity. In any event, he is concerned mainly to show how the changes in outlook of the Enlightenment flowed into diverse social and economic changes, rather than to explain its origins (a matter more for intellectual than economic history, perhaps).

Unfortunately, this leads Mokyr's explanation back into the realm of tautology. The changes in Britain from 1700 to 1850 are presented as mainly an enormous accumulation of “useful knowledge,” and its increasingly rapid dissemination and deployment, in a wide variety of fields. Yet what caused this increase in the rate of knowledge accumulation? It was an increased desire for more knowledge and belief in the efficacy of new knowledge—an outlook that is described as “the Enlightenment.” It is as if the modern world was called into existence simply in a flush of Baconian wish fulfillment! One can see in this a shadow of David Landes's approach—other nations did not industrialize, so they must not have had the same desire for new knowledge as Europeans. No insatiable curiosity, no drive to accomplish new things, hence stagnation.

But this begs all the important questions: Why did Europeans suddenly become dissatisfied with their existing stocks of knowledge? Why did their search for new knowledge turn up so many successful and useful findings, rather than dead ends or superstitious delusions—especially since historians of science have emphasized the enormous amount of mysticism and charlatanry that infused early modern “science?” For that matter, why was Britain so far in the lead within Europe? Mokyr claims that this was not because it was more “Enlightened.” Quite the reverse; much of the Enlightenment flowed stronger intellectually in France and Germany or the Netherlands. But England, we are told, excelled at putting enlightened ideas into practical service because of its plethora of skilled craftsmen. Yet this is odd—if enlightened ideas were rising all across Europe, why didn't craftsmen take their skills where they would get the highest return, namely wherever there were the most productive ideas? But Mokyr notes that even though British craftsmen and British machinery did cross to the continent, for most of the nineteenth century they remained less productive abroad than they were at home. Why was that? Clearly there are issues here yet to be plumbed.

If economists looking for a clear model or a simple explanation of the roots of British industrialization may not be fully satisfied by this book, they should nonetheless read it—if for no other reason than to learn fully the complexities of what they are seeking. The scope and thoroughness of Mokyr's description of Britain's economy in this critical period make it deserving of a place on the shelf of every historian and economist concerned with the origins of modern economic growth; and at $45, Yale University Press is to be commended for putting that goal within reach.