In conversation a few weeks ago I guessed that there were some thirty republican presidential candidates at this point. It turns out I was wrong—as I write this, the actual (and only slightly less absurd) number is seventeen. Being wrong about that didn’t bother me all that much; thirty felt like a true number, but I have now revised my knowledge because I encountered new information.

Revising based on new information is something (I hope) I do quite often. When I want to know something, I try to reason out the answer first, but then go look up the truth. Both parts of that are important—if I look something up without chewing on it first, I tend to forget it easily. If I guess but don’t bother to check my guess then the distinction between estimate and reality is easily lost to memory.

Guessing and revision is a somewhat Bayesian way of encountering the world, but I think it reflects a spirit of inquiry and exploration. In one sense, it is a personal application of the scientific method. In the broadest sense I can envision, it is a fundamental part of human nature to experiment and discover. We all build predictive stories for ourselves about the world to explain what has happened before and help us expect what will happen next.

Sometimes, though, the link between guessing and checking gets lost. Maybe I guess something and forget to check it later, or maybe I hear someone else’s guess and don’t realize that they didn’t check it first. The provisional story starts to lose its hesitancy and become Real, and True, and Important, and other similarly calcifying adjectives. The story developed to model the world starts to become a world in itself. Ideas drift into ideologies.

When I listen to people pushing an ideology, I sometimes hear the ghost of inquiry in the background. They say with certainty the things I want to ask as questions.

“Nuclear power is not a viable option for mitigating climate change.” But I want to ask, “Is nuclear power a viable option for mitigating climate change?”

“GMOs are harmful and can’t help with worldwide hunger and nutrition.” And I think, “Are GMOs harmful, and can they help with worldwide hunger and nutrition?”

“Cutting social security, medicare, and other entitlements is the only way to balance the federal budget.” And I reply, “Is cutting social security, medicare, and other entitlements the only way to balance the federal budget?”

“Environmental concerns have to be economically profitable to be effective.” Do they really, I wonder?

What are these ideas? Guesses we received from others, but didn’t really check? If you ask someone who fervently believes one of these positions to support it, they will, and vigorously. Motivated reasoning is easy, and unfortunately common. But did they ever think to doubt it? Did they look beyond the favored “evidence” swirling around them from people who agree with the idea, and instead seek out some more dispassionate analysis of the facts?

And if I disagree, did I?

I don’t know. I think much less often than I would like. In the words of the old Russian proverb, appropriated by a certain person who largely ignored it in his domestic policies, “trust, but verify.”

So I keep guessing, and I keep checking. My greatest worry is for those ideas that seem immediately true. Such ideas slip easily past our defenses and set up shop in our stories without scrutiny, bending and distorting our subsequent knowledge of the world. There is no way to investigate all of these—we hear them everywhere, and verifying takes effort. We even create them unknowingly.

The only course left to us, I think, is to doubt our own stories along with the stories of others. To breathe that spirit of inquiry back into our ideas, especially when they have died into ideologies. We may always be chasing the truth, but I think that better, on the whole, than embracing fictions.