Nathan Rosenberg, um grande historiador economico - obituario por Joel Mokyr

Eu tinha justo acabado de comprar o livro de Joel Mokyr, The Lever of Riches: Technological Creativity and Economic Progress (num sebo de Amherst, MA), e estava admirando seu trabalho de pesquisa extremamente erudito, que me lembrava justamente o de Birdzell e Rosenberg, How the West Grew Rich, que havia lido primeiro na tradução brasileira, antes de retirá-lo novamente na biblioteca de West Hartford, para citar em um livro que estou preparando.
Os dois, Rosenberg e Mokyr, são os melhores historiadores do progresso tecnológico que conheço, junto com David Landes, mas eu não sabia que Mokyr era sobrinho de Rosenberg, e ele assina aqui um denso e simpático obituário que transcrevo da lista de história econômica.
Paulo Roberto de Almeida

Nathan Rosenberg, 1927-2015
Joel Mokyr
Society for the History of Economics, September 2015

The economic history profession has lost one of its most original, creative, and wide-ranging minds in the passing of Nathan Rosenberg on Aug. 24, 2015. Rosenberg was one of the founding fathers of Cliometrics, a member of the first group of Cliometricians that with coining the term “congregated at Purdue University in the late 1960s, and which included other luminaries among them Lance Davis, Jonathan Hughes, and Stanley Reiter (who is widely credited Cliometrics”). By 1970, this group had moved away from West Lafayette and dispersed to institutions such as Northwestern and CalTech. Rosenberg was hired by the University of Wisconsin, and was a member of a different group of influential and distinguished economic historians in Madison, including at one time or another Jeffrey Williamson, Peter Lindert, Morton Rothstein, Rondo Cameron, and Claudia Goldin. While at Wisconsin, Rosenberg was the editor of the Journal of Economic History and instrumental in its growing focus on the new economic history that was theoretically informed by economics and quantitatively more sophisticated — the very essence of the Cliometric Revolution.
In 1974, Rosenberg moved to Stanford, where he taught for more than a quarter century until his retirement in 2002. As department chair at Stanford between 1983and 1986 he helped build the department and maintain its position as one of the top economics departments in the country. Moreover, his leadership guaranteed that economic history remained an integral part of the undergraduate and Ph.D. programs and includes some of its most distinguished practitioners such as Gavin Wright and Avner Greif, as well as younger and promising scholars. Today, thanks to Rosenberg’s initiative and entrepreneurship, the Stanford department is housed in a gorgeous building named after Ralph Landau, whose support for research and teaching in economics was first stimulated by a fortuitous meeting with Rosenberg. The partnership with Landau, a chemical engineer and entrepreneur fascinated by economics, led to a fruitful scholarly collaboration between him and Rosenberg, especially in two well-regarded collections they edited together. Thanks in large part to Rosenberg’s resourcefulness, the graduate program at Stanford has thrived and produced many distinguished members of the economic history profession and applied economists working on innovation. While not all of them worked with him directly, his influence on the flourishing of economic history at Stanford was undeniable. Many of the former graduate students he trained and inspired co-authored and co-edited papers and books with him, such as David Mowery with whom he wrote Technology and the Pursuit of Economic Growth (Cambridge University Press, 1989). Without exception these young economists admired and adored him; two of them, Scott Stern and Shane Greenstein, were my former colleagues, and the three of us were instrumental in Northwestern awarding him an honorary doctorate in 2006, in the same class of honorary degrees as the then little-known junior senator from Illinois. If ever there was an academic conspiracy that can be called a true labor of love, this was it.

As a scholar, much of Rosenberg’s most important and influential work is captured by the title of his Inside the Black Box, a collection of essays on the nature of technology (Cambridge University Press, 1982). In it, he stated from the onset that “economists have long treated technological phenomena as events transpiring inside a black box...the economics profession has adhered rather strictly to a self-imposed ordinance not to inquire too seriously into what transpires inside that box. The purpose of this book is to break open and to examine the contents of the black box” (p. vii). That metaphor captures the central theme of Rosenberg’s career.

What, then did Rosenberg find inside that black box? In his typical self-deprecating way, he once remarked to me that once you open the big black box of technology, you find inside a smaller black box, and so on, much like Russian matryoshkadolls. Maybe, he reflected, in the end this is what scientific progress really consists of? But of course, opening the black box led Rosenberg to considerably more important insights on the nature of technological change. I will list only a few that I find the most insightful — others can have other preferences. One is his emphasis on the subtle and complex interplay between science and technology stressed in his magnificent essay “How Exogenous is Science?”. In it he points out the many feedback effects that run from technology to science, and debunked the “linear model” that draws the main arrow of causality from Science to Applied Science to Technology. Since Rosenberg’s work, historians of technology have heaped scorn on the linear model. Technology in his view is not the mechanical “application of science” to production; it is a field of knowledge by itself, quite different in its incentives, its modes of transmission, and its culture. It is affected by science, but in turn provides “pure research” with its instruments and much of its agenda. In many cases, he noted, scientists were confronted by the fact that things they had previously declared to be impossible were actually carried out by engineers and mechanics and had to admit somewhat sheepishly that were possible after all. More than a decade later, in his later book Exploring the Black Box, he returned to the important but often-neglected link between technology and scientific progress, provided by scientific instrumentation.

A second item Rosenberg found inside his black box early on was the importance of the machine industry in the generation of technological change and economic growth, a topic he explored early in his career in his influential 1963 Journal of Economic History paper, “Technological Change in the Machine Tool Industry” reprinted in his Perspectives on Technology (Cambridge University Press, 1976). The paper stressed the crucial importance of machine tools in creating the mechanization that was at the heart of the Industrial Revolution in the United States and Britain, and showed that without the improvements in lathes, planers, milling machines and precision grinders, much of the growth of modern manufacturing could not have happened. In his later book Technology and American Economic growth (Harper & Row, 1972) he explained how the ever-growing specialization, and not just the quality improvement and lower prices of these precision metal-cutting and shaping devices, stimulated and supported the rise of modern industry. In his citation for the Leonardo Da Vinci medal that the Society for the History of Technology awarded Rosenberg in 1995, David Hounshell wrote that “His 1963 article remains to this day perhaps the single most influential essay ever written in our discipline. In it, Rosenberg grasped the essential nature of the technical knowledge embedded in the machine tool industry and recognized how that knowledge would not fit easily into existing economic models.”

A third item that many historians of technology, whether economists or not, have found extremely insightful in Rosenberg’s black box is his concept of “focusing devices,” first enunciated in his 1969 Economic Development and Cultural Changepaper “The Direction of Technological Change,” (reprinted in Perspectives on Technology). It is an intuitively powerful concept that essentially proposes that much of technological progress occurs because a firm, a group, or the government realizes that there is an urgent need for a clear solution to a pressing and well-defined social issue or bottleneck in production. The solution is not always forthcoming of course — Rosenberg cited with great glee Hotspur’s decisive riposte to Glendower’s claim that he could call the spirits from the vastly deep: “why, so can I, so can any man; but will they come when you call for them?” (see his Technology and American Growth, p.51). But when the solution is arrived at, it often solves far more than it was intended for and overshoots its target, and thus it creates a new bottleneck. This leapfrogging or “compulsive sequences” phenomenon was used to describe the eighteenth century cotton manufacturing, but in fact it applies to much of the rest of the technological revolutions of the eighteenth century. At the start of the century, British society knew well that it faced a number of hard but well-defined problems: finding longitude at sea, pumping water out of deep-shaft coal mines, ridding society of smallpox, and turning pig iron into wrought iron cheaply and rapidly. By 1800 these problems had all been solved. Rosenberg’s essay deals with firms and their recognition of an opportunity for profit, but one can easily add other motives, from the altruism of Jonas Salk, the driving ambition of James Watson to the political ideology of the men and women working on Project Manhattan.

Academic work was the center of Rosenberg’s life. After his retirement, he continued to write and publish. Together with Bronwyn Hall, he edited the massive two-volume Handbook of the Economics of Innovation (Elsevier, 2010), which contains wonderful survey essays by every serious scholar working in the area. He also published a sparklingly original and creative paper (jointly with Manuel Trajtenberg) in the Journal of Economic History (2004) on the economic significance of the Corliss steam engine and its effect on American industrialization. The brand new Handbook of Cliometrics (2015) contains an essay by Rosenberg jointly with Stanley Engerman on “Innovation in Historical Perspective.”

There was much more to Rosenberg’s intellectual persona than his interest in innovation and technical knowledge. He was fascinated by the “greats” of economics — especially Smith and Marx, on whom he wrote perceptive essays, as well as lesser but equally fascinating figures such as Charles Babbage. He published a collection of his essays on the History of Economics as he saw it (often from the point of view of technology), entitled The Emergence of Economic Ideas: Essays in the History of Economics — idiosyncratic, perhaps, but never dull. In the editors’ introduction to the first volume of the Economics of Innovationcompilation, Rosenberg and Hall cite a long passage from Schumpeter’s preface to the Japanese edition of his 1937 book The Theory of Economic Development.Schumpeter recounted a debate he had with Walras on whether economics should concern itself only with statics or should also be concerned with the rapid changes in the economy. These kinds of historical issues held endless fascination for Rosenberg. The first essay in his published Graz Lectures, Schumpeter and the Endogeneity of Technology: Some American Perspectives (Routledge, 2000), was entitled “Joseph Schumpeter and the Economic Interpretation of History.” He cited at length and with almost palpable delight Schumpeter’s statement that economic history was absolutely required for the scientific study of economics. Rosenberg was also interested in modern medical research and its place in the modern American research university. He surely was the only economic historian to have published a paper both in The New England Journal of Medicine and The Energy Journal (and probably the only one to have published in either).

Rosenberg was one of the broadest and most intellectually curious minds I ever met. He was, as Ken Arrow remarked in his eulogy, an enormous lover of books and owned many thousands of them — yet ironically his own preferred format was the short pointed essay or at most a short and summary book such as his briefTechnology and American Economic Growth. Having read papers on science and technology his entire life, he may have adopted the scientist’s preferred mode of communication over the long and heavily-detailed books written by the typical economic historian. He never wrote a single-authored magnum opus on economic history. The closest he ever came to a big-think ambitious “explanation of everything” was the set of Rosenberg’s lecture notes that L.E. Birdzell collected and then together published as a book How the West Grew Rich. It is a lovely and often insightful book, but it lacks the grandeur and sweep of a David Landes, Douglass North, or Eric Jones, who have written books with similar themes. Rosenberg’s comparative advantage was the brief essay, and the books he published were mostly collections of these essays. These essays were, without exception, beautifully written: he had the gift of expressing a complex and nuanced economic relation in a short and elegant phrase. They are still read by students and scholars all over the world.

As a person, Rosenberg was deeply loved and admired by those who knew him well. He was urbane and erudite even by the high standards of the great economic historians of his generation. He was witty to the point of being hilarious, and could be sarcastic and cutting when he wanted. He was also a deeply caring husband, father and grandfather, the emblematic Jewish father who knew that investment in human capital and family cohesion were the essence of Jewish culture. He was a great colleague and a warm and wonderful friend. Of all the many senior economic historians of that generation whom I knew and admired over the years, he was the only one whom I regarded as much as a relative as a colleague. I will never forget you, Uncle Nate.