But, the reason why we ought to listen to the scientific consensus is not because they are necessarily right, but because they arrived at that opinion through careful consideration of the available evidence. I would even go so far as to say they can be pretty frequently wrong (for years we taught the Central Dogma in biology which, we now know, is not completely accurate), but, because the essence of science is a skeptical/questioning one (as opposed to say religion which is one based on faith and not on testing every thing that is heard), a scientific consensus almost necessarily represents THE BEST OF WHAT WE KNOW. The fact that I can tell you that the Central Dogma is not completely accurate just goes to show that, once evidence for a previously unsupported claim is built, and stands the test of time such that it is NOT rejected by the scientific community, then the claim will build a scientific consensus — and come on, is there any doubt that the scientific community believes in RNA interference and Reverse Transcriptase?

So, it’s not that we ought to value the scientific consensus because its infallible (if that’s the reason anyone’s valuing it, they’ll be pretty disappointed), we ought to value it because of the process by which it’s arrived at representing, in most cases (the issue with naming genes and proteins aside :-D), the only true “marketplace of ideas” in existence today.

I would not say that the consensus expert opinion is frequently wrong. They often get more things right than wrong; it’s just that the errors are the only things that people remember. And improvement on knowledge is inevitable in science; we’re not omniscient beings. We don’t start out with perfect theories. But we do start out with the best theories at the moment, and if I have to choose what theory is more likely to be true at any specific moment in time without any prior knowledge, I’d side with the experts, because I don’t really have any alternative argument. How do I know they’re wrong? I don’t. They might be wrong, but they have an equal or greater chance of being right; that’s what makes them experts.

I would not argue that we know more about medicine than climate science. Medicine is still a vast open desert of knowledge. There is one Earth; there are billions of people, all with different genes, different environments, and different diseases. Most of medicine is extremely experimentally based; there are very few theories or models of how or why something works. They just do it and use it.

And I would argue that a lot of the treatments you mentioned became unnecessary because of advances in technology. Now, we have the ability to detect things with a much higher sensitivity, and our surgical and medical techniques improve such that previous efforts may look barbaric. After all, aspirin, acetaminophen, and ibuprofen are basically obsolete, in that they’d never pass our safety and health requirements today; they were grandfathered in from an earlier, more barbaric time, when people bleeding out their innards was an acceptable risk.

And anyway, the consensus of expert opinion is frequently wrong. We know more about medicine than we know about climate science, and yet, to quote a passage from “Overtreated” by Shannon Brownlee:

“In the latter part of the twentieth century, dozens of common treatments, including tonsillectomy, the hysterectomy, the frontal lobotomy, the radical mastectomy, arthroscopic knee surgery for arthritis, X-ray screening for lung cancer, proton pump inhibitors for ulcers, hormone replacement therapy for menopause, and high-dose chemotherapy for breast cancer, to name just a few, have ultimately been shown to be unnecssary, ineffective, more dangerous than imagined, or sometimes more deadly than the diseases they were meant to treat.”

Would you bet your year-2028 salary that the consensus predictions by today’s climate scientists for the next 20 years will have been found to come true, to within 10% of theirs predictions?

I’m a biologist, and I don’t even know all the stuff happening in biology. I don’t follow immunology very much, for example, and I definitely don’t know enough developmental biology to do stuff there. I don’t know enough chemistry to ask the right questions. I can’t critically review experts in those fields, because I don’t really have any valid points to raise. That’s just in biology; economics, physics, math, history, and so on, I don’t know enough to critically address issues in those fields. All I can do is be curious and ask questions.

So, if everyone had time for infinite discourse, and didn’t have pressing policy issues to resolve and such, and actually had the stamina and the curiosity to understand everything, then sure, take the time, do the discourse so that everyone really understands the issues underlying everything. But really? People don’t. Politicians don’t. And politicians these days, for better or for worse, are being less like a representative republic and more like a puppet for the people. And people don’t care enough to know before they vote.

To see all this, simply look at how the local school boards in Florida are doing with the new state science education standards. Some of them don’t even know what evolution is, and they’re against it. They didn’t take the time to even research what the hell their against!

Yes, scientists are arrogant, and it’s somewhat scientists’ fault that we haven’t educated the public enough. But people, especially leaders, need to start trusting the experts. If even people like George Bush can equivocate about evolution, that’s a strong indicator that he doesn’t care what evidence and the experts say, he believes whatever the hell is most convenient for him to self-affirm his own goals. And that’s a problem.

I know you’re not advocating blind faith here, but I think a large part of the problem is that there’s a level to which scientists lack patience with the general public. It takes time to try and explain anything in great detail, and so it’s very tempting for scientists to oversimplify. If you’re a member of the general public, that’s frustrating. It’s your right and maybe even your duty to question what the experts say. Just because they’re more experienced doesn’t necessarily mean they’re totally right. It just makes it more likely.

Which is not to say that it isn’t useful to have experts, and that we shouldn’t take them seriously. But I think I’d rather have people out there questioning them and their theories before making significant decisions than just saying “Well, this whole field looks reasonable, and they sure know a lot more about it than me, so I’ll go along with it.” It’s arrogant of scientists to assume that the general public should just trust them, and even if they’re right. Part of an expert’s responsibility is to be able to justify themselves to a remotely reasonable lay person.

Which is not to say that every lay person wants to hear what an expert has to say–let me tell you, if I ever don’t want to talk about what I do to a stranger, I tell them I’m an evolutionary biologist. There are some folks who will question me on this, obviously, and want to proselytize to me. And I’m polite to them, because just because my area of expertise is evolutionary biology doesn’t mean I know everything about it. And it drives me crazy that people don’t believe in something that’s been demonstrated so many times, but that doesn’t mean I wish they’d just trust what experts think.

In the end, I think the world is better because people question experts rather then just go along with them. I think reasonable people who use their brains well wind up agreeing with the experts most of the time anyway and that that. Frankly, the problem is more that a lot of the people out there aren’t like that, but the ones who are make what the experts spend their lives obsessing over legitimate.