Who Trusts Science? Do I Trust Science?

Lots of chatter on the web today about this graph, from a new article in the American Sociological Review about Americans' attitudes toward science. It shows that since 1974, conservatives had gone from having the most trust in science to the least. The author offers this possible explanation:

In the past, the scientific community was viewed as concerned primarily with macro structural matters such as winning the space race. Today, conservatives perceive the scientific community as more focused on regulatory matters such as stopping industry from producing too much carbon dioxide.

Ok, maybe the switch from scientist as builder of nuclear bombs to scientist as prophet of ecological doom does play a role here. And no doubt evolution also has an impact, since there isn't anything scientists are more certain of. Right now the relationship between science and American conservatives is rocky, and maybe to a dangerous degree.

I would enjoy being able to join the chorus of liberals crowing about how much more in tune with science their ideas are, and how you can only be a conservative by ignoring the findings of science, etc. The thing is, I don't know that I "trust science." What does that mean?

I do believe that science, performed properly, is the best way we have to find out about the world. I think science has discovered many truths about the universe. I believe in evolution by natural selection; I think the earth is billions of years old; I think we are made of atoms.

But when it comes to the topics that are the subject of public debate, I am not sure that scientists always have more to offer than anyone else. Climate change is Example A. I am concerned about what all that CO2 in the air will do to the climate, and I wish we weren't doing such a drastic experiment with the only atmosphere we have, but I think all those curves showing how many degrees the mean temperature will increase and how many meters sea level will rise are just guesses. Educated guesses, maybe, but guesses all the same. And when I see scientists fulminating in print about how denying global warming is like denying the Holocaust, I think that the rest of us should exercise a healthy skepticism.

Real scientists ought to understand that certain knowledge is very hard to come by. Evolution, yes; that is an idea tested and explored in a hundred thousand ways over 150 years, meeting every challenge. Atomic theory. Nuclear decay. But do antidepressants cure depression? Is homosexuality genetic? Is vegetarianism good for your heart? Does dioxin cause cancer? Will climate change cause a mass extinction? Do dams "destroy" river systems? On these and thousands of other questions scientists have taken strong public stands on both sides with very little evidence. Scanning back over all the pronouncements made by scientists in the past 200 years is a sobering experience. To paraphrase Seneca, there is nothing so stupid that some scientist has not defended it as the infallible finding of science.

Scientists are every bit as subject to fads and political fancies as other people. They ought not let that get in the way of reading the data, but sometimes they do. Everybody ought to trust some of science's findings, but everybody ought also to be wary of the things scientists say, especially when they are in the grip of political enthusiasm.