Kevin, you’ve stirred up quite a spat with the left-wing blogosphere concerning how much we should care about the scientific views of politicians, with specific reference to the cases of global warming and evolution. I’m very sympathetic with your frustrations, but I’d put a similar objection somewhat differently. What I think would be most helpful in this discussion is rigor in defining the boundaries of science.

Physical science has enormous, justified prestige as an intellectual discipline that has created vast improvements in our material standard of living. Progressives routinely attempt to drape the label “science” over assertions that do not have the same reliability as physical science in order to create political advantage. This occurs in two dimensions.

First, scientific findings in some area are used to justify some related political or moral opinion. Key examples are exactly the topics you touch upon: global warming and evolution. In one example, the indisputable scientific finding that CO2 molecules redirect infrared radiation is used to argue that “science says” we must implement a massive global program of emissions mitigation, when in fact, the argument for this depends upon all kinds of beliefs about the growth of the global economy, Chinese politics, technological developments and so on for something like the next couple of hundred years. In the other example, the incredibly powerful scientific paradigm of evolution through natural selection is used to argue that “science says” we have just eliminated the need for God in the creation of the human species, when in fact, as a simple counter-example, the genetic operators of selection, crossover, and mutation require building blocks as starting points, and therefore leave the classic First Cause argument unaddressed.

Neither the Left nor the Right is guiltless here. The Left attempts to stretch science to justify what are really non-scientific viewpoints, but conservatives often react by attacking the underlying science, rather than making the more complicated — but more accurate — point that the actual scientific findings published in peer-reviewed journals (i.e., “the science”) don’t really imply the political assertion. 

In the second dimension, fields such as economics that lack the reliability of physical science are often treated by partisans on both sides of the aisle as if they should speak with scientific authority. Macroeconomics is not valueless, but we should not grant its assertions the same rational deference that we grant to those made by physical chemistry. 

The role of rational politicians, then, is to have an understanding of the boundaries of actual scientific expertise and accept consensus scientific findings within these fields as practical “givens” in determining policy — but not to be snowed by everybody with a bunch of equations into accepting their personal politics as indisputable by any rational human.