You could choose from among a seemingly infinite number of issues, but let’s mention just two that have been in the news recently: The unrest and violence in Ferguson, Missouri and Baltimore, Maryland. Liberals and conservatives both argue that they reveal structural problems in our nation. But that’s where the agreement ends and the real arguments begin.

In each instance, those in opposing ideological camps have drawn completely different lessons from what occurred. For liberals, the two incidents highlight racial divisions, problems with law enforcement and lack of spending. For conservatives, they underscore anti-police bias, liberal failures and the harmful effects of broken and never-formed families.

In the case of Ferguson, both sides saw what they wanted to see. Conservatives pointed to the fact that Officer Darren Wilson was justified in shooting Michael Brown and that the “hands up, don’t shoot” narrative was false. Liberals pointed to a Department of Justice report showing that in nearly every aspect of Ferguson’s law enforcement system, African Americans are impacted in a negative and unfair way. The result is that both sides talk past each other.

These are but two examples of an endless, recurring dance in American politics, in which event after event is used to confirm what we already believe. Time and again incidents merely justify our pre-existing views. I’ve seen this happen to people whose views I disagreed with; to people whose views I share; and to me. You may even have experienced it happening to you.

What cognitive scientists call confirmation bias is an unavoidable feature of political life. It often plays out in the almost instantaneous reaction most of us have when our views are challenged. We go in search of data and arguments not to learn so much as to confirm. Sure we already possess the truth, we’re not interested in processing inconvenient facts; we want to refute them.

Implicitly, the thinking process goes something like this: “I don’t want my opponents’ claim to be true. It therefore can’t be true. Now let me find evidence to prove it’s untrue.” If we heard ourselves or others say such a thing, we would be appalled. But here’s the dirty little secret: Everyone acts this way some of the time, even if we don’t publicly admit it.

Under the influence of this cast of mind, politics takes on a zero-sum quality. Once someone settles on a point of view, all the arguments of those with whom they disagree must be discredited. So if you’re in favor of tighter gun control, every argument the NRA makes must be wrong and every study that shows gun control laws doesn’t reduce crime must be dismissed. And if you believe anthropogenic global warming is a hoax, every claim by the world’s major science academies needs to be challenged and explained away as evidence of pervasive corruption. To make it so, you’ll believe arguments so thin you’d never take them seriously on most subjects, and you’ll desperately search for any hole, however small, in the arguments of an opponent so that you don’t have to face the core of his case.

Confirmation bias is something we can easily identify in others but find very difficult to detect in ourselves. (If you finish this piece thinking only of the blindness of those who disagree with you, you are proving my point.) And while some people are far more prone to it than others, it’s something none of us is fully free of. We all hold certain philosophical assumptions, whether we’re fully aware of them or not, and they create a prism through which we interpret events. Often those assumptions are not arrived at through empiricism; they are grounded in moral intuitions. And moral intuitions, while not sub-rational, are shaped by things other than facts and figures. “The heart has its reasons which reason itself does not know,” Pascal wrote. And often the heart is right.

Without such core intuitions, we could not hope to make sense of the world. But these intuitions do not stay broad and implicit: we use them to make concrete judgments in life. The consequences of those judgments offer real-world tests of our assumptions, and if we refuse to learn from the results then we have no hope of improving our judgments in the future.

Politics isn’t (and shouldn’t be) some kind of technical exercise. It is properly also an arena of moral judgment and philosophical disagreement. But it is an arena in which our views are tested in practice, and so we have to allow it to be a venue for learning from experience. For that to happen, we need to leave our intellectual cul-de-sacs from time to time, and to allow at least a few unlike-minded people to have standing in our lives and, when necessary, challenge our interpretation of things. “If you bring people together who disagree,” Jonathan Haidt, author of The Righteous Mind: Why Good People Are Divided by Politics and Religion, has said, “and they have a sense of friendship, family, having something in common, having an institution to preserve, they can challenge each other’s reason.”

Acknowledging the existence of confirmation bias is not enough. In fact, that alone can lead us to become only more cynical and closed-minded. Seeing the limits of our knowledge would, in a perfect world, make us humble, not arrogant. We have to see that the existence of such bias doesn’t mean that no one’s arguments are ever true; it only means that no one’s—not even yours or mine—are always true. The truth exists, but none of us fully apprehends it. At best, we see only parts of the whole, which is why our politics will always be properly partisan.

But the fact of that partisanship—that politics consists of groups locked in debate, each possessed of part of the truth—makes it even harder to overcome our biases. The desire to defend our “team” is often an even more powerful inducement to ignore contrary arguments than the desire to confirm our own personal assumptions.

This fact is surely an obstacle to a rational democratic politics. And if confirmation bias has always been with us, it appears to be more prevalent today than in the past. According to the Pew Research Center, “Republicans and Democrats are more divided along ideological lines – and partisan antipathy is deeper and more extensive – than at any point in the last two decades.” Anecdotal evidence by lawmakers, who report unprecedented levels of polarization, reinforces this finding.

But the solution is not to despair of self-government. In fact, the answer is less cynicism, not more: We should not conclude that no one makes rational arguments in our politics, but rather than even people we disagree with make rational arguments, and so perhaps we should hold our views a little more lightly than we do and try to be less sure and to listen.

This isn’t an argument for being perennially uncertain; nor does it mean that all of us share the same amount of wisdom or that we’re all equidistant from the truth. Some people are a good deal closer to it than others. We should, however, be more willing to hold up our views to refinement, and to acknowledge the ubiquity of human limitations. We should go into arguments believing we have something to learn.

This really should be easier for us – for me — than it tends to be. And the reason it’s so hard should also make us humbler. The fact is that we are frequently not interested enough in deepening our understanding of things. We enter politics like lawyers looking to win a case for our clients no matter what, rather than like citizens looking to improve our common lot—or like seekers after wisdom looking to better understand the world. That has a lot to do with why our politics so often become personal, polarized, and heated.

To close off the possibility of change, self-reflection, and self-criticism is to elevate ideology over truth and to disfigure reality in the service of dogmatism. There is quite enough of that going on already.

But in the end, we must remember that precisely because no one knows the whole truth, even a more honest, wisdom-seeking democratic politics will always be partisan. Our dynamic, diverse country will always be full of people who disagree with you, and you will always worry about what might happen if they win the next election. That’s why fully recognizing the ubiquity of confirmation bias should ultimately leave us grateful, including for a system of government that tries not to give any person, party, or institution too much power all at once. And grateful for a constitution built upon a deeper recognition that most of us ever possess of the limits of human knowledge and the depths of human imperfection.