Even the most rational of us have superstitions, and superstition doesn’t have to mean throwing salt over your shoulder or your toenail clippings on the fire. Whether it’s avoiding doing something so as not to jinx yourself or believing in the power of a lucky piece of clothing to influence events there is at least one irrational belief hiding somewhere in most of us.  But in increasingly rational times why do we still keep hold of superstition?

At its most basic it’s because of the way that our brains are wired.  Tens of thousands of years of evolution have seen countless of our ancestors faced with uncertainty or danger.  Those who were cautious and learned to associate hazard and risk with certain signals and events were those who survived to pass on their genes and behaviours.  Natural selection, in favouring those whose risk taking was appropriate, also favoured the superstitious and over cautious.

There are two rather contrasting examples of how we view this behaviour.  When a flock of birds scatter and fly off following a sudden noise we don’t describe them as ‘superstitious’.  The adaptive behaviour that they show to risk though is exactly the same that sees some people use alternative medicine.  Many accept the lack of scientific basis, independent proof, or anecdotal nature of the evidence on the basis that using alternative medicine can have little risk but carry the possibility of substantial benefits if it does work.

This same behaviour is seen in modern superstitions.  We may not consciously believe that if we don’t forward a chain email to twenty friends that harm will befall us, but we can be fairly sure that if we do there’ll be no great disadvantage to us either.  Indulging in the superstition about chain letters and emails also touches on another evolutionary reason for belief in superstition – that at heart we are social animals.  Complying with superstitious behaviour is a way of explicitly demonstrating our adherence to the wider customs and beliefs of the group as a whole.  This can then become self-reinforcing as individual behaviour creates a degree of ‘group think’ that in turn revalidates individuals’ beliefs.

As in so much of our behaviour, confirmation bias also plays a large part in superstition.  We subconsciously choose to only remember or accept evidence that confirms our beliefs, and this is how we confirm that our lucky mascot (whether it’s an item of clothing, an object, or even a behaviour) does indeed work.  We remember having it when things went well, and still cast a positive light on less successful occasions where we had it with us.  At the same time we remember times that went badly where the lucky charm was absent, and gloss over completely any successes that occurred without it.  This self-reinforcing belief can directly influence our behaviour as well, leading us to dread an event where we don’t have the lucky object with us.  As a result we behave negatively and our discomfort and lack of success only confirm the power of the object to bring us good fortune.

That our capacity for superstition overrides our rational side was demonstrated by Bruce Hood, the author of Supersense.  During a talk he produced a fountain pen that he said had belonged to Albert Einstein, and audience members were keen to touch and handle it.  He then produced a jumper that he said had belonged to another famous figure, and asked who would like to wear it.  After any initial reluctance at the condition of the jumper had been overcome with the offer of fifty dollars there would normally be a substantial number of volunteers.  His then telling the audience that the jumper had belonged to Jeffrey Dahmer saw the majority of raised hands being rapidly pulled down.

The reasons people gave for changing their mind – that the jumper might somehow be contaminated, that other members of the audience wouldn’t approve – were all to some extent attempts to justify an instinctual response, a response that is as strong now as any previous generation’s superstition.

If you’re still congratulating yourself on your rationalism then why not read about confidence tricks and find out why your being clever is no defence against them.

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