The Becker-Posner blog continues to provide new evidence that a keen mind, logical thinking, and the ability to come up with fresh insights are no more a prerequisite for success in academia than elsewhere.

I am thinking in particular of the latest series of posts on global warming. Posner, while indicating his tepid support for the Kyoto protocol, proceeds to recite the typical criticisms. One of these is that while the costs associated with the implementation of the protocol are substantial, the result will be a relatively small slowdown of global warming.

It is not difficult to see that this objection is beside the point. If global warming is a serious problem that must be stopped to avoid likely disaster - as is the scientific consensus and as Posner accepts without objection - then actions that slow it down should are valuable steps forward. If Posner believes that the Kyoto protocol does not do enough - as many environmentalists do - then the logical step is to support the protocol, and then support additional measures after its passage. Incidentally, this is the very purpose of the Kyoto Protocol - it was conceived not as a solitary move to fight global warming but rather the first in a series of steps. I get the feeling Posner does not know this.

Posner continues, arguing that if we accept that most of the really serious damage due to climate change will occur towards the end of the century, then Kyoto would be too much:

For by that time science, without prodding by governments, is likely to have developed economical “clean” substitutes for fossil fuels (we already have a clean substitute—nuclear power) and even economic technology for either preventing carbon dioxide from being emitted into the atmosphere by the burning of fossil fuels or for removing it from the atmosphere.

One wonders if Posner has some sort of crystal ball which allows him to gaze into the future. Certainly, it would be wonderful if we developed technologies which will allow us to instantly solve the global warming problem, but we obviously don't know that we will. Posner claims that this outcome is "likely." How did he decide this? What analysis did he perform? Rationally, because we have no idea whether the sort of technologies Posner describes will be developed, it makes quite a bit of sense to take prudent action here and now.

Posner then ends his post by mentioning the possibility that global warming will produce abrupt climate changes in the near future. This seems to be the main reason for his support of Kyoto.

But even this proves to be too much for Becker who, while accepting the danger and science of global warming, opposes the Kyoto protocol because it gives the underdeveloped nations too many exemptions for Becker's taste. Becker then goes to propose a different agreement, where underdeveloped nations would be held to the same standard, but allowed to sell their emissions credits resulting in a substantial flow of money from the first world to the third; this flow of money would give incentives for nations in the third world to agree to Becker's proposed treaty.

This is profoundly unhelpful. The idea of emissions trading has been tossed around for a while and plays a part in Kyoto; the point is, whatever the merits of Becker's proposed agreement, we don't have it. We have Kyoto: the agreement reached by the international community. Becker presents the dilemma to us as a choice between Kyoto and some other proposals; but our dilemma is purely a yes/no choice on Kyoto. In this way, Becker avoids the obvious conclusion that, given all we know, the benefits of Kyoto in terms of climate change clearly outweigh the cost.

Becker then proceeds to criticize Posner's concern with abrupt climate change, arguing

...a few naturally induced rapid climate changes in the course of thousands of years does not mean that the man-made risk of such a dramatic change should receive much weight. Given all the risks the world faces, such as terrorist control of nuclear and biological weapons, or runaway nanotechnology, genetically modified crops, and cloning-all very well discussed in Posner’s new book Catastrophe- I believe he is excessively concerned about climatic catastrophes. options.”

This, again, is clearly a non-sequitur. Terrorist control of nuclear weapons is an important problem, but its existence does not mean that global warming has become less dangerous! The world faces many risks, as Becker correctly indicates, but this is not an argument for avoiding this one particular risk.