Expertise is not transitive

Lawyers are experts on the law and one seeks a lawyer to advice on a legal issue. Doctors are experts on medicine and one seeks a doctor to advise on medical issues. There are few people who are expert in both the law and medicine. Generally one should not consult a lawyer for diagnosis of a health problem, nor a doctor for prescription of a course of action to deal with a legal problem.

George H. W. Bush was a fighter pilot and did a great job as president organizing a coalition to conduct a war on Iraq, limiting that war when it had achieved its specified objectives. George W. Bush was a fighter pilot and did a lousy job as president organizing a coalition to conduct a war on Iraq, leading to a long term occupation with shifting objectives. Thus, logically we can not conclude that being a fighter pilot is or is not related to one's ability as president to conduct a war successfully in Iraq.

This all seems painfully obvious, but apparently it is not well and widely understood that expertise in one field does not imply expertise in another field. Indeed, if one spends the time and effort to gain real expertise in one field it would seem unlikely that one would also have spent the time and effort to become an expert in other fields as well.

In my recent posting on science advice I mentioned that it is important to structure the advisory process correctly. Very few scientists are expert diplomats or expert military strategists or tacticians, so it is not a good idea to ask them for advice on diplomacy or military tactics. One might ask a panel of epidemiologists about the health conditions that soldier might face in a campaign or about the health impacts from a trade agreement and expect good advice within the panel's area of expertise. The panel might very well go beyond that scope and give unrequested advice on campaign strategy or negotiating tactics, but that advice would be of untested quality. Ideally decision makers should not ignore such unrequested advice, but rather test it against the advice of military or diplomatic experts.

It seems to me that it was correct to say that John McCain's training as a fighter pilot and his service to his country, while deserving respect, are not necessarily very important qualifications for the presidency. Those factors may be more important as indications of character, and a person's character does seem very important in judging whether one will vote for the person. (Didn't someone say that FDR was a man with a second class brain, but a first class character?)

I am impressed by Obama's efforts to draw the Democratic party together behind his candidacy. I think that effort displays elements of political leadership needed by a president. Moreover, while a president is important for setting the tone and "fronting" for his administration, running the government of the United States well requires a big, competent team. Obama seems to be working to put together the best team his party can field.