I think the really big factor here is that scientists don't want to go into politics! Maybe I'm painting the world with an overly broad brush here, but politics and science approach the truth in exactly opposite ways.<p>I'm not going to say that politics is a game of lies, because it's not, but politicians essentially invent the truth as they go along. It's similar in some ways to law or the humanities, where the truth is very much a matter of interpretation, there's a case to be made for each side, and no one is ever objectively "wrong". Right and wrong are entirely a matter of personal opinion.<p>On the other hand, science is, in the limit, entirely objective. A physical theory can be objectively shown to be incorrect. Scientists can defend their theories, but fundamentally have to accept it if their theory is disproved, or else they become irrelevant. There was a great link earlier today on HN that talked about how the smartest people are the ones who are most skeptical of their own ideas. That's great in science, but if you don't believe yourself totally in politics, no one else will.<p>This means that scientists, who presumably study under and work with other scientists for decades, think in this scientific mindset. This makes them totally unsuited for the world of politics (and of course, vice versa). Politicians can't admit they were wrong, because that means that they'll probably be wrong again, and no one will vote for someone who's wrong. Case in point: Mitt Romney and universal healthcare.<p>I'll also make another point that a lot of people miss: Being a politician is roughly as difficult as being a scientist. If we expect our best politicians to get an advanced degree in something like business or law (things related to the process of running a nation) or to spend a long time working in politics or on social issues, why do we think that scientists with no such training will make good politicians? We certainly don't expect most law school grads to do much more than wash bottles in the lab.