I am not referring to subtle scientific points like relativistic physics, which medical treatment works slightly better, or whether an exposure causes measurable cancer risk decades in the future. These are phenomena where people’s intuitions are not so good because the phenomenon is difficult to see. Nor am I talking about sciences that are so politicized, like economics, that people think they know things that are actually contrary to what they have observed. I am talking about phenomena that are either simply observable and/or have been worked out by people developing a technology. It is quite important to make this distinction because errors in intuition from the former categories are often used an excuse for not recognizing that most matters fall into the latter categories.
The example that led me to make this observation was a story about some research that showed that 4- to 6-year-olds prefer breakfast cereal that comes in boxes with pictures of favorite cartoon characters. In this case the result (that kids presented with a taste of a moderately healthy cereal from a cartooned box rated it higher than kids who got the same cereal from a cartoon-free box) conformed to our intuition. What if it had suggested otherwise? Then the sensible thing would have been to not believe it. The observation that kids like the cartoons conforms to what everyday observation and the development of marketing technology already told us.
This contrasts with the other major breakfast cereal story of the week, just to add some cereal serial, where there is a concern in the UK about whether the cardboard packaging made from recycled newspapers creates a health hazard because of the mineral oil residue in it. That is a case where we should understand that intuition is worthless, both the the intuition of those who shriek, “chemicals! it has chemicals in it!”, and those who insist that all such worries are naive. The theme of the recent stories is to deny that there is a problem. But it is actually pretty funny because the pundits whose politics drives them to a knee-jerk objection to the public worrying about chemicals tend to be the same ones who think that recycling is not worthwhile either. Also kind of funny was the way the story ended, due to an editing error:
Weetabix said it was
That is the end of the online Guardian article at the time I am writing this (sadly, they might fix it later). I quite like Weetabix, and really missed it for the many years between when I studied in England and it became available in America, but I would still be genuinely surprised if Weetabix (a) had this kind of Cartesian awareness or (b) could communicate it. On the other hand, if it did and could, it seems like just the type of cereal that would have such an existential attitude.
Ok, getting back to today’s relatively dull theme (yesterday left me wanting my blog posts to all be comedy – I should probably not try too hard), I am reminded of the anti-tobacco extremists who try to convince people that cartoon characters or scenes in movies are what make 18-year-olds want to smoke, or that e-cigarettes attract nonsmokers, or that nicotine has no value. I think of wind turbine proponents who tell people who can hear the pulsating noise from the turbine that was installed near their house, “no, according to my acoustical modeling, you are not hearing a noise that is driving you mad.” Who should you believe, their model or your own lyin’ ears? In all of these cases, the advocates create scientific “evidence” that contradicts the more natural knowledge and try to convince people that it trumps natural knowledge because in some quite different situations studies do trump common knowledge.
Early in the UN series I had a couple of posts about Daryl Bem’s ESP research that purports to show that people can, to a very small but measurable extent, “remember” highly memorable stimuli from a little bit in the future. Commentators were apoplectic about this, and made points like “extraordinary claims require extraordinary evidence”. That is certainly a reasonable point, but which is a more extraordinary claim: That there is a small-magnitude phenomenon buried in the barely-understood phenomenon of consciousness that defies our current understanding, or that despite the thoughtful and reported experience of countless nicotine users, that it really produces no benefits?
To put this in Bayesian terms, our prior beliefs are that the future cannot affect our current perceptions, but that is an assumption that we should be willing to let evidence override (a weak prior). But our prior beliefs that 5-year-olds like cartoons, 18-year-olds are pretty indifferent about cartoons, people know when a noise is driving them crazy, and people know when they like a drug – based on the experience of thousands or millions of people – are very strong priors, and we should not make the mistake of letting one small artificial study sway us much. If there is a pattern of the systematic studies contradicting the common knowledge, then we need to think hard about which is right. But if they agree, we should not forget where our real knowledge comes from; the real reason we know that kids like cartoons has nothing to do with any lab experiment.