From Science Magazine comes this report about the Pew Research Center’s survey results on public opinions of scientists.  (HT to Overecoming Bias.)

This graph shows the poll results of scientists’ political ideologies, compared to the public’s perception of scientists’ political ideologies.

And this graph compares scientists’ party affiliations with those of the general public:

So the public perceives that scientists are far more neutral (or perhaps just more apolitical) than scientists actually are. And scientists as a whole are overwhelmingly more liberal than the general public.

Which brings up a few interesting questions.

Why are scientists overwhelmingly liberal?

My own hypothesis is that it’s a combination of three primary factors (plus, probably a multitude of smaller factors which I’m ignoring here). Pardon the broad brush with which I’m painting:

  1. Scientists are inherent believers in the power of intelligence. They have faith in the ability of smart people to solve complex problems, centrally plan things, and try out new ideas. This makes them natural progressives. The conservative worldview is unattractive to scientists because conservatives prefer the tried-and-true, and will generally choose facts over theories.
  2. Scientists work in or closely with academia, which is overwhelmingly liberal.
  3. The Republican party is increasingly regarded as being somewhat hostile towards science, and GOP members have taken stances on topics such as stem cell research, evolution, and global warming that most scientists disagree with.

Why does the public believe scientists are so neutral?

My hypothesis: it’s a form of the appeal to authority fallacy. The public believes scientists are neutral because THEY’RE FREAKIN’ SCIENTISTS. They must be neutral, right? They are supposed to be pursuing the objective truth in their scientific endeavors. Surely this unbiased neutrality spills over into areas other than their scientific specialties, right? Like, say, politics?

And finally…

What is the take-away from all this?

The public’s uncritical faith in the neutrality of scientists is unwarranted, and the public needs to exercise a healthy dose of skepticism about scientific claims that have not yet withstood the test of time — particularly scientific claims regarding politically charged topics such as global warming. There is a wealth of information suggesting that scientists cannot overcome their own biases even within their own specialty, and it only gets worse when they express their opinions on subjects outside their areas of expertise. For more detail, I would refer you to the excellent book “When Good Thinking Goes Bad: How Your Brain Can Have A Mind Of Its Own” by Todd Riniolo. He cites numerous studies revealing the cognitive biases and belief-reinforcing behaviors of scientists, and gives examples of famous highly regarded critical thinkers who nevertheless held indefensible politically-motivated beliefs, even in the face of strong contradictory evidence. (Isaac Asimov and Albert Einstein are two of the figures he mentions in this context.)