Lots of bloggers identify with the "reality-based community." At first glance, it's a rather cultish self-description; after all, even the "faith-based community" thinks it's "reality-based." (Ever seen the bumper sticker where the Jesus fish marked "Truth" swallows the Darwinian land-fish?)
On further consideration, though, the label actually means something. If you say you belong to the reality-based community, you practically have to believe that if other people knew what you know, they would favor different policies.
For example: If you as a member of the reality-based community make a big deal out of the fact that Saddam Hussein had nothing to do with the 9/11 attacks, you practically have to believe that if other people admitted this fact, they would have been less likely to support the Iraq War.
Similarly, if you as a member of the reality-based community make a big deal out of the fact that immigrants have a small effect on American wages, you practically have to believe that if other people admitted this fact, they would be less opposed to immigration.
Obvious? Apparently not. Here's how Steven White of the American Prospect reacted to my Cato talk (coming eventually to C-SPAN's BookTV):
It's easy to think economists have all the right answers when you're an economist in a room full of people that agree with you. But it probably strikes most average people as absurd. These people aren't irrational. They just have different values.
I've heard this story before. I don't deny that different values explain some fraction of political disagreement. But quotes like this suggest that different values are the sole reason for political disagreement.
That's just crazy. Would opponents of the teaching of evolution keep resisting if you convinced them that evolution were true? Would opponents of immigration stand their ground if you convinced them that immigration makes 90% of native-born Americans better off? Indeed, how many people who favored the Iraq War would have changed their position if they foresaw what actually happened?
The lesson is that the reality-based community already implicitly rejects what I call the Myth of the Rational Voter. The reality-based community questions many popular beliefs about how the world works, and thinks that changing those beliefs will change many popular beliefs about what policies we should have.
In short, if differing values explained all political disagrement, the reality-based community is wasting it's time. Why argue about the facts, if the facts have nothing to do with people's policy positions anyway?