I used to share the physics envy of many economists. The responses to Bjorn Llomborg’s book have helped change my mind.
Along with many economists, I suffered for years from physics envy. I wished that economists could bring to their subject the rigour, and the focus on falsifiable experiment, characteristic of the natural sciences. But I’ve been cured. The Bjorn Lomborg affair has played a large role in the cure.
Lomborg is a Danish statistician, the author of a polemical attack on what he calls ‘the litany’ – a collection of widely disseminated claims about environmental deterioration. Lomborg’s book was published in England at about the same time as E.O. Wilson’s the Future of Life. The two books, pitched at a similar popular level, lie at opposite ends of the spectrum of environmentalist views. Wilson’s style is moving, almost lyrical, while Lomborg’s prose is plodding; Lomborg’s book is, however, more tightly argued and extensively referenced.
The reactions to Lomborg were, from the beginning, odd. Criticism was aimed not at Lomborg’s work, but at Lomborg himself. Wilson and other American scientists attacked Cambridge University Press for publishing it. Scientific American published a symposium which contained much sound and fury but signified very little. A buffoon planted a custard pie in Lomborg’s face in an Oxford bookstore, an incident strangely reminiscent of the one in which water was poured over Wilson’s head at a meeting of the American Association for the Advancement of Science.
But the most peculiar response of all came from the Danish Committee on Scientific Dishonesty. I confess my first reaction was to suppose that this organisation was a spoof. Its report tends to confirm that impression. But it really exists, and I suppose such organisations are necessary. In the light of scandals such as Sir Cyril Birt’s falsification of intelligence research and the supposed invention of cold fusion, only collective action by the scientific community can ensure integrity in reports of primary research findings.
The Danish Committee on Scientific Dishonesty did not undertake any investigation of Lomborg’s primary research – reasonably enough, since he did not claim to have undertaken any. Less reasonably, it did not undertake any investigation at all, simply reproducing verbatim assertions made in Scientific American. The style of its approach can be illustrated with one example, made much of in the Committee’s Report.
Lomborg claims that a widely cited estimate by Norman Myers – that species are becoming extinct at the rate of 40,000 a year – has no scientific basis, and was simply a number made up in order to attract attention. This is a serious accusation, but it appears to be in all essentials true. In the current state of knowledge, there is no means of estimating, even to an order of magnitude, how many species exist in the world or the numbers of them which disappear. More recent estimates have tended to focus, not on the absolute number of extinctions, but on the ratio of that number to some base level: although the evidentiary basis of these figures also seems to be extremely weak (see Wilson, p. xx, for a description)
Myers is close to the line in terms of scientific dishonesty, although since he does not actually claim that his number is based on substantive research he probably falls on the right side of it. Incredibly, however, the charge is levelled, not at Myers for making the number of 40000 up, but at Lomborg for pointing out that he had done so. The Committee finds Lomborg guilty of scientific dishonesty in failing to acknowledge that Myers ‘deserves credit for being the first to say the number was large and for doing so at a time when it was difficult to make more accurate assessments’.
It is kinder at this point to leave the Danish Committee on Scientific Dishonesty alone. One might have expected that serious scientists would have denounced its absurd proceedings, but in fact the only public comments from the scientific community seem to have been supportive. The principal criticism of the Committee’s report has come from economic journalists – The Economist magazine and Martin Wolf in the Financial Times. And for a well argued criticism of Lomborg’s conclusions on climate change, you should look, not to Scientific American, but to the critique in Prospect by Adair Turner, economist and banker.
What is going on? The proceedings of the Committee, and the rants in Scientific American, have nothing to do with the evaluation of scientific evidence: they are affirmations of tribal loyalty. Scientific American actually headed its symposium ‘science defends itself’. The Danish Committee rambles disapprovingly about the reporting of Lomborg’s work in Time magazine, as if that would somehow be relevant to whether it constituted scientific dishonesty. For such people, as for George Bush and Donald Rumsfeld, the world divides into goodies and baddies, and the only important issue is which side you are on. And if you are on the wrong side, off to Guantanemo Bay: evidence and due process are for wimps.
The lesson I have learned is that the skills needed to handle questions of moral or political controversy are much rarer, and more difficult to acquire, than I had imagined. All of us come to these issues contaminated by background and prejudice. Sound training in economics, in history, in philosophy or in law helps us to handle that contamination. There are still too many partisan historians and economists, biased lawyers and bad philosophers: the results of that training are by no means always effective. It is much easier to ask ‘is he one of us?’ Still, the best social scientists bring rigour and logic to issues that others find difficult to argue dispassionately or resolve objectively.
But most natural scientists have not experienced training in handling practical controversy, and many of them do not have the ability to do so. Perhaps that is how it should be: without his obvious passion for the natural environment, Wilson might never have completed either his meticulous work on the social behaviour of insects or his imaginative efforts to promote the unity of the sciences. But the corollary is that scientists have a much smaller contribution than they think to make to issues of science policy. And that economists have distinctive capabilities to be proud of after all.