Michael Shermer has a nice piece in Scientific American on confirmation bias, the process “whereby we seek and find confirmatory evidence in support of already existing beliefs and ignore or reinterpret disconfirmatory evidence.” New neuroimaging studies are revealing exactly how it is that we avoid actually thinking about politics. Psychologist Drew Westin says:

Essentially, it appears as if partisans twirl the cognitive kaleidoscope until they get the conclusions they want, and then they get massively reinforced for it, with the elimination of negative emotional states and activation of positive ones.

I think this process is especially fascinating to libertarians like Shermer and me who stand on the sidelines of partisan political tribal warfare. Not that libertarians aren’t guilty of confirmation bias—everyone is. It’s just that less is at stake for libertarians; we don’t have any power to lose. Reinforcing and encouraging this specific kind of unreason is one way political coalitions assure their integrity and survival. The day-in-day-out work of partisan political magazines is to explain to its loyal readers why there is basically no reason to take the other side’s so-called arguments seriously. All you need to know about the minimum wage, say, is that there is someone good at math at Princeton who thinks it’s good, and that everyone who dislikes it secretly wants to send the poor to forced labor camps. Or all you need to know about people who oppose the war is that they are flag-burning America-haters whose pusillanimous “post-modern” sense of moral equivalence leads them to secretly crave the reign of jihadist overlords. Etc.

As the scientists show, when confronted with a position contrary to our own, we don’t even think, we just feel our way to our dogmas, and we feel good about it. In a country, like ours, where there is actually a rather surprising broad consensus surrounding a great number of issues, survival as a distinct political coalition with a distinct identity may require getting the most polarizing mileage possible out of people’s tendency toward confirmation bias. That may not be ideal for democracy.

But confirmation bias matters not only because rationality matters, but because autonomy matters. Last week I attended an Institute for Humane Studies seminar at Stanford, and philosopher David Schmidtz gave a talk about psychological freedom—freedom from internal contraints. He remarked that there is something pretty depressing about the fact that what we believe is largely a function of the order in which we encountered new ideas—that our commitments are highly path dependent. But the fact that we can know that holds out hope for a kind of liberation.

So, this Independence Day, why not pick up a political book you know you’ll disagree with. Or write a short essay giving the best argument you can think of for a position you find abhorrent. Or really listen to what your annoying brother-in-law thinks about the war at the family picnic. We could all be a little more rational, and a little more free, if only we really wanted to be. Dogmatic, whole-hearted commitment does feel good. But there is more to life than feeling good. There is truth, for one thing. And there is freedom—self-command. We’re all jerked around by our own minds. But we can be jerked around less.

Shermer concludes, “Skepticism is the antidote for the confirmation bias.” Now, we don’t all need to be like Socrates, claiming to know about nothing at all. But a little intellectual humility goes a long way.