In reference to Jonah’s post below, I find it interesting that so many are willing to point to the critiques of Bjorn Lomborg published in various places without having read Lomborg’s responses. This makes a difference. Take the review in Science as an example. The reviewer gives Lomborg a generally negative assessment yet, in the process, makes several clear errors, such as claiming that Lomborg fails to cite sources that are clearly cited, or fails to discuss matters that are clearly discussed. Many of the critiques found at www.anti-lomborg.com have the same problem, as I discovered when trying to discuss some of this material with my students. But don’t just take my word for it, check it out for yourself, something Lomborg has made quite easy to do (and without buying the book) by posting the most prominent critiques — and his responses — here.