I’m educated and a fan of science. So why do I follow superstitions?

As kids, many of us are told that if we go outside with wet hair, we’ll catch a cold. And as adults, we might spend an extra few minutes drying our hair before stepping out.

Many tall buildings in Anglo countries don’t label the 13th floor, while buildings in East Asia often skip floor four.

If a player I barrack for is having a winning streak, and a commentator mentions it, I might feel like the player is “jinxed” and their winning streak will end.

These are all common superstitious and traditional beliefs (that used to be called “old wives’ tales”). And no matter how science-literate our society is, they persist. Let’s look at why, and whether there’s any harm in them.

Origins in older belief systems

The belief about catching a cold from wet hair has roots in ancient Greek and Chinese medicine. Health was based on balance and harmony, with the temperature of our bodies and our environment playing important roles.

Now we know viral exposure is the crucial factor.

Some recent research does show the respiratory tracts of mice appear more vulnerable to viruses in colder environments. But even if we’re more vulnerable to viruses when cold, it doesn’t mean wet hair is specifically risky.

Why do superstitions persist today

The psychology of “sense making” – how we make sense of the world and our lives – helps explain our behaviour. Throughout human history, people have come up with explanations for the origins of the universe, their lives, and why things are the way they are.

Some claim the drive for sense making is a fundamental motivation, similar to hunger or loneliness. But having a drive to explain the world doesn’t guarantee our explanations will be accurate.

The knowledge we draw on at any moment typically isn’t rigorously based on evidence and sound logic. It’s more like little puzzle pieces, stored in disorganised piles in the backs of our minds.

We may keep some pieces from science class in one corner, alongside a pile of information passed down from our grandparents. When we need to explain something, we quickly try to put those pieces together.

How science and the supernatural can fit together

We can be quite creative in how we assemble information, in ways that are totally incompatible with science.

Research from rural South Africa a few years after the peak of the AIDS crisis revealed how human minds do this. Before public health education to fight the spread of the HIV virus, people often believed AIDS was caused by witchcraft.

After these education programs, the idea of a sexually transmitted virus did not supplant the role of bewitchment. Instead the two fit together. Someone might believe witchcraft caused the attraction that lead to sex with someone carrying the virus, for example.

The researchers called this “explanatory coexistence” because scientific explanations (the virus) and supernatural explanations (here, witchcraft) happily coexist in our minds.

It can be risky when it becomes pseudoscience

Sometimes science-ish explanations sound plausible because our knowledge is very shallow and a “pseudoscientific” claim may be based on some scientific components.

When it comes to catching colds, while I know a virus causes the cold, my knowledge doesn’t go much deeper. So it may not be too hard to convince me of some phoney but science-ish explanation or treatment.

Early in the COVID pandemic, for instance, people took the idea that bleach and sunlight can kill bugs and wrongly applied this to COVID. Myths that drinking bleach or sitting in the sun could clear a COVID infection spread among family and friendship groups, as well as social media.

We trust others to form our beliefs because we believe they may know more about that topic than we do, whether they be doctors or our grandparents. Anecdotes have a big influence on our judgements, even when we are presented with evidence to the contrary.

Should I rein it in?

To work out if it’s a problem to mix scientific beliefs with the supernatural and superstitious, we have to consider what behaviours it leads to.

There’s no harm drying your hair before going outside or getting mad at a sports broadcaster after your team blows their lead. There may be safety benefits in avoiding walking under ladders, or opening umbrellas indoors.

If it’s just a bit of fun, like doing tarot readings at a party, it’s not something you need to worry about. But if you won’t go on a date with someone you really like because you’re a Scorpio and they’re a Gemini, it might be worth rethinking your position.

Interrogating your beliefs – and why you believe something – is a good way to start. By understanding what you don’t know and trying to fill your knowledge gaps with credible sources, you will improve your collection of puzzle pieces, and develop better ways of fitting them together.