When someone believes something about you, good or bad, you’ll always end up proving them right!

I RECENTLY met up with a group of people I’d known years ago. We all got a little tipsy and even though much time had elapsed since we’d seen each other, they felt comfortable enough to chide me. ‘‘Yes, but you’re the type of person who…” ‘‘Tell Ruth that story, she loves that sort of thing . . . Ruth’s a party girl…’’

I found it all very odd at first since I wasn’t quite sure what they meant. And then I worked it out. They were talking about a Ruth they knew a decade ago. And although so much had changed over 10 years, they were guilty of what so many of us are guilty of: primacy error.

Primacy error is an irrational process where the brain remembers its first impressions of a person’s traits and gets locked into its original opinion. Examples of primacy error are: ‘‘Jenny is mean with money’’; ‘‘Simon isn’t that bright’’; ‘‘It’s always grey and cold in Melbourne’’. The error doesn’t make rational sense. Jenny may well have been mean at one stage, but may have been short of money at the time, and is now comfortable. Simon may have had depression at the time he was judged. He then went on to invent the internet. Melbourne can have lovely days too.

But still the primacy error remains, according to Stuart Sutherland, author of Irrationality: The Enemy Within. Evidence doesn’t come into the equation. And even if Jenny bought a hospital for sick kids, there would still be scepticism. Must be a tax deduction. Or Simon just met up with clever people who pushed him through.

These first impressions, which are formed immediately or over the first period of a relationship, don’t take into account that 10 years later someone may well have earned their stripes, had therapy, had a baby, a breakdown, a breakthrough, gone on Ritalin, grown up, gone mad. People change.

The irony about primacy error is that when people believe something about you, you’ll always end up proving them right when they’re about. My mum always warns me to be careful when I’m clearing her table. I must have been clumsy as a child. Who would ever have believed that over several decades I’d learned to use both my right and left hands, together. ‘‘Careful, careful,’’ she mumbled recently, which was like: ‘‘Don’t think of pink elephants!’’ Smash!

We are often irrational and unfair. Perhaps a small pause before generalisations might allow us to be very pleasantly surprised. Share your stories of primacy error with me. Does your mother; partner or friends believe something about you from 100 years ago?

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