In my own work, I have speculated that an extreme version of this phenomenon is operative in obsessive compulsive disorder, a condition that affects millions of Americans. In many cases of O.C.D., patients are paralyzed with doubt about some fact — against all evidence. For example, a patient might doubt whether she turned off her stove despite having just checked multiple times. As with skeptical pressure cases, the focus on the possibility that one might be wrong plays a central role in the phenomenon.
Let’s return to climate change skepticism. According to social psychology, climate change deniers tend to espouse conservative views, which suggests that party ideology is partly responsible for these attitudes. I think that we should also think about the philosophical nature of skeptical reactions, an apolitical phenomenon.
The standard response by climate skeptics is a lot like our reaction to skeptical pressure cases. Climate skeptics understand that 97 percent of scientists disagree with them, but they focus on the very tiny fraction of holdouts. As in the lottery case, this focus might be enough to sustain their skepticism. We have seen this pattern before. Anti-vaccine proponents, for example, aware that medical professionals disagree with their position, focus on any bit of fringe research that might say otherwise.
Skeptical allure can be gripping. Piling on more evidence does not typically shake you out of it, just as making it even more probable that you will lose the lottery does not all of a sudden make you feel like you know your ticket is a loser.
One way to counter the effects of skepticism is to stop talking about “knowledge” and switch to talking about probabilities. Instead of saying that you don’t know some claim, try to estimate the probability that it is true. As hedge fund managers, economists, policy researchers, doctors and bookmakers have long been aware, the way to make decisions while managing risk is through probabilities. Once we switch to this perspective, claims to “not know,” like those made by Trump, lose their force and we are pushed to think more carefully about the existing data and engage in cost-benefit analyses.
Interestingly, people in the grips of skepticism are often still willing to accept the objective probabilities. Think about the lottery case again. Although you find it hard to say you know the shopper will lose the lottery, you readily agree that it is still very probable that he will lose. What this suggests is that even climate skeptics could budge on their esteemed likelihood of climate change without renouncing their initial skepticism. It’s easy to say you don’t know, but it’s harder to commit to an actual low probability estimate in the face of overwhelming contrary evidence.
Socrates was correct that awareness of one’s ignorance is virtuous, but philosophers have subsequently uncovered many pitfalls associated with claims of ignorance. An appreciation of these issues can help elevate public discourse on important topics, including the future of our planet.
N. Ángel Pinillos is a professor of philosophy in the School of Historical, Philosophical and Religious Studies at Arizona State University.
Now in print: “Modern Ethics in 77 Arguments” and “The Stone Reader: Modern Philosophy in 133 Arguments,” with essays from the series, edited by Peter Catapano and Simon Critchley, published by Liveright Books.
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