Skepticism About Skepticism

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Calling someone a "skeptic" can be a term of praise or condemnation.

Too often, it expresses approval when the target of skepticism is a claim we reject, and disapproval when the target is a claim we hold dear. I might praise skepticism towards homeopathic medicine, but disdain skepticism towards human evolution. Someone with a very different set of beliefs might praise skepticism regarding the moon landing, but disdain skepticism regarding the existence of God.

Sometimes, though, skepticism is taken to be a healthy attitude towards belief — a characteristic that we might praise regardless of its target. Skepticism is supposed to reflect a willingness to question and doubt — a key characteristic of scientific thinking. Skepticism encourages us to look at the evidence critically; it allows for the possibility that we are wrong. It seems like a win, then, to learn that courses in skepticism can decrease belief in the paranormal or — as reported in an article forthcoming in Science & Education — that teaching students to think critically about history can decrease belief in pseudoscience and other unwarranted claims.

But taken too far, skepticism misses its mark. It's important to avoid the error of believing something we ought not to believe, but it's also important to avoid the error of failing to believe that which we should. If the aim is to detect signal — and not merely to reject noise — then an educational win would require greater differentiation between warranted and unwarranted claims, not merely rejection of the unwarranted. This point is sometimes lost in praising skepticism and skeptical thinking, with its emphasis on what we reject rather than what we uphold.

It's important to say that this isn't intended as a criticism of the skeptical movement or of skeptical philosophy, both of which endorse more nuanced versions of what skepticism entails. It is, however, a criticism of the way skepticism (as used in casual conversation) is sometimes held up as a virtue in itself. The virtues we should really be upholding — and for which skepticism is only an oblique guide — are what I'll call truth-tracking and humility.

Truth-tracking is about getting things right: identifying the signal amidst the noise. We don't want to be fooled by noise (about a link between vaccines and autism, for example), but we also don't want to miss out on signal (about the real benefits of vaccination). Truth-tracking isn't (only) about rejecting noise, but about differentiating signal from noise.

Humility is about recognizing the possibility for error, and therefore holding beliefs tentatively (or "defeasibly"). But recognizing uncertainty doesn't mean that all bets are off. Some bets are still much better than other bets. You don't know who will win the next horserace, for example, but that doesn't mean that you'd assign equal probabilities to all contenders. Similarly, we can quantify uncertainty by assigning degrees of belief to different propositions. I might think that life on other planets is unlikely, and that ESP is unlikely, yet assign a much higher probability to the former than to the latter. Similarly, I might think that rain tomorrow and human evolution are highly likely, but assign a much higher probability to the latter than to the former. Quantifying uncertainty allows us to hold even strong beliefs with a modicum of doubt, while simultaneously recognizing that they're far more likely than the alternatives we defeasibly reject.

Skepticism is a poor proxy for truth-tracking and humility. It gets us half of truth-tracking (rejecting noise), and it gets us some of humility (questioning and doubt). What it doesn't get us is signal with degrees of belief or — more ambitiously — truth in an uncertain world. That seems like a more praiseworthy aim to me.

Tania Lombrozo is a psychology professor at the University of California, Berkeley. She writes about psychology, cognitive science and philosophy, with occasional forays into parenting and veganism. You can keep up with more of what she is thinking on Twitter: @TaniaLombrozo