Seems like more people I know are dying. In this case it is a good friend of mine and occasional coauthor, the Swedish economist, Tonu Puu, who was born in Estonia of an Estonian father and a mother of German ancestry. As it was, he ended up speaking a very large number of languages, as well as being very cosmopolitan in many other ways. He was 83 years old and had cancer for some time, which is what I presume he did of, although the announcement did not specify a cause, but it happened this past Saturday in Umea in northern Sweden, where he was at the university there for most of his career.
Before talking about his work in economics, I want to note that probably more important for him was music. He made baroque instruments such as viols and harpsichords, and was so good at it that professional musicians had him make such instruments for them. For many years he ran an annual Baroque music festival that attracted fine musicians from all over the world to Umea. I shall note here that an important characteristic of Tonu, which some of you may not like, was that he was deeply conservative in many ways. A sign of this in music is that he considered Beethoven to be the "worst thing that ever happened to music," at least I heard him say that. He saw Beethoven as being ultimately responsible for there being rock concerts in Venice that knocked off parts of the roof of the opera house. I happen to disagree with that, seeing that as a pretty shaky link, but this was the sort of long-run perspective that he took to many things, full of his own integrity that ignored popular and transient trends, even if those were centuries long.
As a segue to talking about his economics, I note that he focused most of his attention on writing books, which are his most cited works, and covered not only many areas of economics in them, but also wrote on interdisciplinary matters. Thus one of his later books, which went into a second edition, is Arts, Sciences, and Economics: A Historical Safari, Springer (almost all his books were published by Springer), 2006, 2015, with him also being a deep student of the history of technology.
As noted he wrote on many things, but he is probably best known for something I am also into: nonlinear economic dynamics, with him applying these ideas to various parts of economics, including industrial organization, urban and regional economics, macroeconomic dynamics, international and interregional trade, and even capital theory, with over 100 articles and into the teens of books, with several of them going into multiple editions. His most cited are Nonlinear Economic Dynamics (first edition, 1989, not sure how many of them), Attractors, Bifurcations, and Chaos: Nonlinear Phenomena in Economics (3 editions,first in 2000), Mathematical Location and Land Use: An Introduction (2nd edition, 2003, not sure when first was), and Spatial Economics: Density, Potential, and Flow, coauthored with the late Martin Beckmann in 1984 (this one by North-Holland). In that one and in a few articles earlier, he presaged Paul Krugman in presenting rigorous and highly innovative models urban and regional models with economies of scale, work that Krugman never cited or recognized, although this was half of what Krugman got his Nobel Prize for. Tonu's final book came out in 2018, Disequilbrium Economics..
His most cited articles were involved applying nonlinear dynamics to industrial organization problems, such as his 1995 paper on "The Chaotic Monopolist," which appeared in Chaos, Solitons, and Fractals, a journal he served as the first economics coeditor of.. He tended to publish his papers in odd journals, many of them not strictly in economics, such as Environment and Planning A and Geographical Analysis. I note that in that paper he followed up on Joan Robinson's 1933 point that monopolists may face non-monotonic marginal revenue curves. While he was generally conservative, he paid no attention to ideology in his economics work and drew from many sources and inspirations. I think that he supported the more conservative parties in Sweden, although those tend to be to the left of the US Democratic Party. In any case, most of his macroeconomic models drew on the nonlinear Keynesian ones by people like Hicks and Goodwin.
Besides his original work on nonlinear location theory models, and his chaos theory analysis of industrial organization, another original model he developed was the first analysis of the possibility of chaotic hysteresis in business cycles. He more or less laid this out in the first edition of his Nonlinear Economic Dynamics book, his most cited work, but the full development of it appeared as the first artcle to appear in the journal Occasional Paper Series on Socio-Spatial Dynamics, which would later become Discrte Dynamics in Nature and Society. The paper is "A Chaotic Model of the Business Cycle," 1(1), 1-19. Later I and some others would empircally find evidence for such a pattern in Soviet investment patterns, of all things.
He also founded the ongoing Nonlinear Economic Dynamics Society (of which I am Chair of its Executive Committee) and also CERUM at Umea University. I am not sure what that acronym stands for precisely, but it is a center devoted to research in regional economics, and it was his final professional location. The announcement of his death came from its current director, Lars Westin.
I shall close this by quoting at length from his view on publishing and how it has changed, comparing how things used to be in Europe compared to now, especially under the influence of American academia, with this showing also showing both his integral conservatism and view of standards.This is from pp. 31-32 of his book, Arts, Sciences, and Economics: A Historical Safari, 2006 edition, and it also gives a flavor of his persona, I think.
"European university culture, until the 1960s, heavily depended on seminars, where various members of the staff, working with entirely different topics, communicated their results. For that reason, the staff members had to keep a broad perspective on their disciplines. Relatively little was regarded as being worth publishing, and national and local 'schools' were established, which made visits toother universities really interesting.
We tend to look down on the previous generation as they published relatively little. This fact, however, does not imply that the worked little or were less creative. It might just signify that they were more choosy about what they regarded as being significant enough to merit publication.
After large scale production ideals from the US overtook the European style, everything is produced for immediate publication, even the relatively insignificant ideas. If it is publishable, it is not insignificant, and the number of journals will expand to allow ever-increasing publications. The number of journals, which has exploded accordingly, conveniently provides for the space. We still have seminars, but we read already published or accepted papers, which we do not want to criticize, and we hardly expect anybody else at the department to understand our whole message. Travel and change of department only results in new personal relations, not new ideas; it may be that we would urgently need more interdisciplinary scientific fora in the future just in order to provide for encounters with the unexpected ideas we need to secure creativity."
I close by noting that an extreme example of his older view is shown by Piero Sraffa, who took 35 years to finally publish in 1960 his magnum opus, reportedly only after many efforts by Joan Robinson, the not-quite-even 100 page long Production of Commodities by Commodities: A Prelude to a Critique of Economic Theory.
Anyway, RIP, my old friend, Tonu Puu (and there should be an umlaut over that "o" in his name.)