Following some vigorous exchanges, we seem, surprisingly enough, to have come close to a consensus about the range of scientific views on global warming. All contributors to the debate, notably including Ken Parish, seem to agree that my proposed statement of the Global Warming hypothesis:

GWH: Human activity has contributed to global warming over the past century, and, in the absence of policy responses, is likely to generate additional warming of at least 1 degree C over the next century

is broad enough to encompass the views of all the serious contributors to the climate science component of the debate, including moderate sceptics like Richard Lindzen. In particular, all serious contributors to the debate agree, at least on the balance of probabilities, that the evidence supports human-induced global warming.

So the big question for debate is how much warming the “business as usual” scenario will lead to. The range
(a) around 1 degree – the skeptical view
(b) 1 to 3.5 degrees – the mainstream IPCC view
(c) 3.5 -5 degrees – the worst-case view (e.g Stephen Schneider)
From what I can see, effects like substantial species extinction, destruction of natural ecosystems, flooding etc are likely to be severe if the warming exceeds 2 degrees, and warming of 5 degrees would produce widespread human catastrophe.
Which of these is right depends on complex arguments about feedbacks and so on, on which aren’t going to be resolved in a hurry. But the existence of uncertainty cuts both ways. Things might turn out better than the IPCC expects, but they could also be worse.
So the question is, what do we do in the face of this kind of uncertainty. There are both philosophical and practical issues here. Philosophically, there’s a choice between ‘precautionary’ and ‘permissive’ principles. The precautionary principle says we should minimise environmental risk in cases of uncertainty, the permissive principle says we shouldn’t restrict economic activity unless it’s been proven to be harmful.
I prefer a practical rather than a philosophical approach. Will it be cheaper, on average, to do nothing now and take really drastic action in a shorter timeframe if the warming turns out to be in the upper range of predictions, or to start now with Kyoto and take the risk that costs will have been incurred for nothing if the sceptics turn out to be right? Given the difficulty of doing anything fast that’s already been demonstrated, I think the latter approach is justified.

An interesting piece from Daniel Gross at Slate, looks at the declining fortunes of Edison (a for-profit schools company, listed on NASDAQ) and concludes that for-profit (or at least corporate) education is inherently uneconomic. I agree, with the caveat that narrowly focused vocational training can be delivered on a for-profit basis, as witness the ‘University’ of Phoenix (the scare quotes reflect the fact that this institution would probably not qualify as a university in Australia or many US states).

There’s been an interesting debate within the Catallaxy collective concerning inheritance taxes, affirmative action and related topics. Without covering all of the issues let me make a couple of observations. First, as David Friedman observes, efficiency arguments are based on the presumption that, if we always choose the policy that maximises aggregate dollar benefits, gains and losses to individuals will cancel out over time, leaving everyone better off than under any plausible alternative rule. This argument clearly doesn’t apply if much of one’s life chances are inherited or otherwise determined at birth. So, to my mind, efficiency arguments against inheritance taxes are doomed from the start.
Second, this debate raises questions about the idea, popular in Third Way circles, that we can forget about equality of outcomes and focus on equality of opporunity. Given highly unequal outcomes in one generation, the successful members of that generation will find ways to give their children a headstart. Hence, equality of opportunity can’t coexist with ‘too much” inequality of outcomes.

Ken Parish sensibly declines my challenge to find 50 climate scientists opposed to the global warming hypothesis, but continues to deny that there is a scientific consensus on the subject. So let me sharpen things up a bit. I assert that at least 95 per cent of climate scientists (and probably 99 per cent) accept the global warming hypothesis, as defined below

To back up my claims, I’ll offer a version of the challenge in which I do the heavy work. I invite Ken (or anyone) to provide a list of independent climate scientists opposed to, or sceptical of, the global warming hypothesis, stated as follows
GWH: Human activity has contributed to global warming over the past century, and, in the absence of policy responses, is likely to generate additional warming of at least 1 degree C over the next century
To recapulate, qualified experts must:
(i) hold an academic or equivalent position in climate science or some closely related field such as meteorology or oceanography (as opposed to, say, areas of physics unrelated to climate modelling)
(ii) have no conflict of interest, such as employment by fossil fuel companies or thinktanks with a stated viewpoint on the issue
For each name supplied, I’ll either
(a) object on grounds (i) or (ii), or failure to demonstrate scepticism
(b) supply 20 names of similarly qualified supporters of GWH, with backup
Assuming I can keep up my end of the challenge, the ratio supports my estimate of 95 per cent support for GWH
(Note: I have deleted a comparison with anti-evolution sceptics which I thought on reflection was unreasonable)

As I’m well aware, petitions and counterpetitions are controversial. So before raising some issues with Ken Parish about the Leipzig and Oregon statements on global warming, I want to make a few things clear.
First, climate change is too important to be left to the experts. Everyone should have their say on this topic. But, if people want to call themselves “scientists” or “economists” they should be prepared to have their qualifications scrutinised.
Second, criticism of qualifications and motives is not a legitimate reason for ignoring arguments (the ad hominem fallacy). But it is a perfectly reasonable response to another ‘use with care’ rhetorical device, the argument from authority, as in “over 17,000 scientists declare that global warming is a lie with no scientific basis whatsoever.”
Third, among those who can reasonably be classed as experts, it’s a mistake to give too much weight to active researchers on a particular topic. It’s easy for a research community to develop the same kind of taboos as any other community, obvious to outsiders but unchallengeable within the group. Others in the same discipline often provide a more realistic perspective.
Finally, there’s nothing inherently wrong with partisanship and there’s nothing immoral about conflicts of interests, as long as they are openly declared. I’m obviously partisan on a number of issues, and, like most economists, I’ve done some consulting. I try to be upfront about this and to argue honestly at all times. But it’s obvious that a new study from me, finding that some particular privatisation was a bad idea, would be received differently from a similar study from an equally prominent economist who was not identified with any particular viewpoint or interest group.
With these caveats, let’s look at the Leipzig and Oregon statements. Both are typically presented as evidence that there is significant disagreement among scientists about the global warming hypothesis. For someone’s opinion to count on this score, I think they should:
(i) be an expert in the relevant field, that is, hold an academic or equivalent position in climate science or some closely related field such as meteorology or oceanography (as opposed to, say, areas of physics unrelated to climate modelling)
(ii) have no conflict of interest, such as employment by fossil fuel companies or thinktanks with a stated viewpoint on the issue
The Leipzig declaration was made in 1997, and relies in part on some outdated arguments, such as the satellite data I discussed previously. More relevantly, of the 100 or so signatories, I can’t identify more than 30 who meet criteria (i) and (ii), even applied loosely. The balance is made up of people like consultants, retired physicists and (I am not making this up!) TV weathermen.
The Oregon petition, with nearly 20000 signatures is harder to assess. Anyone who claimed to have university-level qualifications in science was invited to sign – the criteria would include me, and most members of my family, although I have only one relative who would normally be called a ‘scientist’. In fact, the list includes quite a few cases where whole families seem to have signed.
It seems reasonable to focus on the subgroup (about 2600) who claim to be “physicists, geophysicists, climatologists, meteorologists, oceanographers, and environmental scientists”. Of these, less than half the signatories claimed a PhD, which is a basic requirement for a serious scientific job in the US. I Googled a sample of about 30 PhD’s of whom none were climate scientists (only about half met the much broader stated description). They included petroleum geologists, physicists working in weapons labs and others with research fields very distant from climate science. I also emailed the petition organisers, asking for a list of climate scientists who had signed, and got no reply.
Based on this sample analysis, I doubt that there are more than 50 independent climate scientists in the world who could be regarded as overt critics of the global warming hypothesis. This is a relatively easy claim to refute, if anyone cares to go through the Oregon list and the various ‘skeptical’ sites, and produce more than 50 names fitting criteria (i) and (ii) above. Thanks to Google, all that would be required is an Internet connection and few hours of boring work.
It’s natural to ask how the Australian economists petition, which I helped to organise, stands up against the criteria I’ve set out. All of the signatories meet criterion (i), and none, so far as I am aware, has a direct financial conflict of interest. Some prominent signatories, including Clive Hamilton and myself, are well-known supporters of environmentalist and social-democratic views, and are associated with bodies like the Australia Institute. On the other hand, others like Peter Dixon and John Hewson are well-known advocates of free-market views. The total number of signatories, nearly 300 with some late entries, is also fairly impressive, given that there are only about 1000 academic economists in Australia, and the response rate to mass mailings of any kind is usually about 40 per cent.
Of course, it may well be that the counterpetition being promoted by my colleague Alex Robson will achieve a similar response. If so a majority of the profession will have displayed a view one way or the other. This would certainly speak volumes for the public-spiritedness of Australian academic economists.

Back in 1994, when John Langmore and I wrote Work for All, we pointed out the massive increase in the number of older men receiving what is now the Disability Support Pension, and observed that this was a form of hidden unemployment. Similar disguised unemployment is present in a number of European countries, including the UK and the Netherlands. But until I read this piece, I wasn’t aware that the same thing was happening in the US. Even though the US isn’t unique, this further undermines the claims that flexible US labour markets are the way to solve unemployment problems. The increase in disability and imprisonment in the US over the last decade amounts to 3 or 4 per cent of the workforce, suggesting that any realistic estimate of US unemployment rates is in double digits.

FORTUNE points out that the trillion-dollar losses in telecoms outweigh anything in the dotcoms or Enron by an order of magnitude. Regular readers of this blog will remember I made this point a few weeks ago, referring back to a February Op-Ed piece for the Fin, entitled Pop! There goes a trillion, and a bit earlier referring to a piece published back in February 2001, where I observed that “the downturn has spread from the flashy but economically inconsequential dotcoms to the large, and massively indebted, telecom sector”.
Blogging, where you read tomorrow’s headlines today!

Ken Parish has a fascinating piece on the very limited impact of postmodernism on judicial decisions in Australia and the US. Economics is similar, in that postmodernism has had almost zero impact. I did a literature search for Foucault, Derrida etc a while back, and, outside some peripheral fields like marketing, there was absolutely nothing. This is surprising , since a lot of postmodernism rests on economic claims about modernity, globalisation and so on. Ken dismisses postmodernism as useless, but I can think of at least three good uses
(i) Therapy for recovering Stalinists
(ii) A harmless target on which right-wing pundits can vent their rage
(iii) Some theoretical content for degrees in “communications”
I’m particularly keen on (iii), for the reasons set out by Deirdre Macken in the weekend Fin (subscription required). As a columnist, it’s hard enough hanging on to my space against the usual competitors. Imagine if all those communications graduates had actually been taught how to write a coherent argument,.

As predicted, Mickey Kaus loves the spin in the latest NYT column on welfare reform, and considers that a brief mention in para 7 constitutes “fair play” for the left. He doesn’t discuss the rising demands on private charity, but comes close with his suggestion that the former welfare recipients are now eligible for unemployment insurance. In reality, the proportion of US workers covered by unemployment insurance is at an all-time low.

One Market under God by Thomas Frank, and The Free-Market Innovation Machine by William Baumol. I’ll be reviewing them for The Drawing Board: An Australian Review of Public Affairs, having already done a brief note on Frank for BOSS (the AFR magazine).
I’m going to be disappointingly predictable on this one. Frank’s anticapitalist manifesto is brilliant and Baumol’s paean to the market is far below his usual standard. In particular, how, in 2002, can you write a book on innovation that contains three passing references to the Internet?