Why do people believe dangerous, anti-scientific nonsense, such as the claim that vaccines cause autism, or that climate change isn’t real? The usual answer is some combination of stupidity, misinformation and an unwillingness to face scary truths. But at the risk of making myself as popular as Gwyneth Paltrow at a meeting of the General Medical Council, I’d like to suggest another: common sense. After all, the idea that it might be advisable to stab children with disease-ridden needles is plainly absurd. Equally bizarre is the notion that mere humans could alter the planet – our entire, incomprehensibly enormous planet! – just by burning things. And don’t get me started on pasteurisation. For milk to stay safe, as everyone knows, you have to keep it cold, not heat it up! Talk about magical thinking.

Yes, yes, obviously I know all these objections are wrong. But as the psychologist Andrew Shtulman explains in his fascinating recent book Scienceblind, you needn’t be stupid to entertain them. You are simply in the grip of your “intuitive theories” about reality – the ideas we get from our upbringing, maybe our genes, and above all from the experiments we run on the world from the moment we’re born. Every infant is a tiny physicist, biologist and sociologist, developing unspoken theories to help them navigate life. Babies soon conclude, for example, that one solid object can’t pass through another. (In studies, they’re puzzled and curious when shown illusions suggesting otherwise.) Long before we’re taught about molecules, we come to think of heat as if it were a substance, which can hop from a flame to your hand, or waft away when you open the window. Inaccurate, but it works. As does the idea of avoiding sharp needles containing germs – until, one day, it doesn’t.

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Some of our theories get corrected early. Four-year-olds believe that if you have three birthday parties in one year, you’ll end up older than your peers; but by the time they’re seven, children know that’s incorrect. Other theories linger into adulthood. Shtulman reminds readers of an old riddle: which is heavier, a pound of feathers or a pound of gold? You know it’s a trick. But you probably felt a little inner tug toward answering “gold”. That feeling is your intuitive theory about heft and bulk – learned as a baby, or maybe hardwired – interfering with your intellectual understanding of weight.

Vaccination, global warming, the fact that the earth orbits the sun: all of these require us to suppress intuition – which makes it easier to see how, given various other circumstances, you might end up doubting the science. None of this makes anti-vaxxers or climate-change deniers any less wrong, but it never hurts to grasp where people are coming from.

And maybe I’m not so different. I know climate change is real and vaccines are safe – but deep down, in my gut, I still suspect electricity may be leaking out of unused sockets around my house. It just feels like it makes sense, you know?

oliver.burkeman@theguardian.com