Scott Adams (of Dilbert Fame) has a great post today on the rationality of trusting the experts. While Scott is specifically talking about listening to the advice of economists (which he has surveyed) in regards to figuring out which US presidential candidate has a better plan for the economy, his advice holds true for virtually any complex issue such as climate change. As I have argued frequently in the past, when an issue is so complex that non-experts (like you and me) have no chance to understand it completely (or even be able to construct a reasonably complete picture) it makes little sense to challenge the mainstream scientific (aka expert) opinion.
If a weather expert tells you what the weather will be on a specific day next year, you can safely ignore him. If he tells you a hurricane is heading your way, it’s a good idea to get out of the way, even if the storm ends up turning. That’s playing the odds.
Likewise, if an economist tries to tell you where the stock market will be in a year, you can safely ignore that. But if he tells you a gas tax holiday is an unambiguously bad idea, that’s worth listening to, especially if economists on both sides of the aisle agree.
If you think it is okay to ignore economists because they are so often wrong, you’re looking at the wrong questions. Economists are generally wrong with complicated models but right about concepts. For example, they know that additional domestic drilling won’t make much of a dent in the energy problem. And they know that free trade is generally good for all economies. (You can argue with my examples, but the point is that some things are generally known by economists while not being understood by the general public.)
By analogy, a mechanic knows that changing your oil is good for your engine, but he can’t tell you what problems you will have with your car next year. You shouldn’t ignore the mechanic’s advice on changing oil just because he doesn’t know when your battery will die, or because he didn’t personally perform any scientific studies on oil changes.
Doctors are often wrong, but you are still better off going to the doctor than diagnosing problems yourself. And when you get the opinions of several doctors, your odds improve, even if those several doctors aren’t a scientific sample. The important thing is that following a doctor’s advice, or the consensus of several doctors, increases your odds compared to the alternative. And the more doctors the better.