People interested in politics spend a lot of time talking about what will happen in the future. Speculating about the plausibility of different scenarios is a mainstay of political conversation. Looking back at an event after it’s happened, like UKIP’s success in the local elections, we tend to see the outcome as inevitable. We pick out events that lead to the outcome we now know – like Nigel Farage doing well in the debates with Nick Clegg – and we retrospectively assign them greater importance than we would have done before we knew the result. In experiments, people adopt this “creeping determinism” without realising that they have.
Well I didn’t see the extent of this UKIP win coming but that’s not surprising. Most of my knowledge about politics comes from having earned my living as a political hack. When we learn from experience, we tend to underweight unlikely events. Suppose the true probability is that there will be a car crash on my street once every ten years. If I’m learning from experience, I’ve lived here for a few years and I’ve never seen a car crash, so I will think that they are less likely than they really are. One problem that people like me – people who have worked in or write about politics day-in, day out – need to overcome is that we always expect the obvious thing to happen. Most of the time, we’re right about that – but not as often as we predict.
If you learn your probabilities from reading about the situation, you make the opposite mistake. You tend to overestimate how likely an unlikely event is, especially if it’s an exciting, emotionally involving one. If you read that the chance of your aeroplane crashing is one in one million, you will act as if it’s much more likely than that. It’s this tendency, I think, which leads people who comment on politics from the outside or at the beginnings of their career to focus on unlikely possibilities: Labour winning a majority built from the left, Britain leaving the European Union and so on.
Both groups fall for wishful thinking too, of course, but I’ve already done one blogpost on the false consensus effect.
Wherever you put yourself on the spectrum from naïve amateur to blinkered hack, if you’re trying to work out how likely it is that Labour will win the election, or that Nick Clegg will resign or that Michael Gove will become foreign secretary, think about whether you might be overweighting or underweighting rare events. Once things have happened, remember that your mind will try and convince you that it was destiny and that the tell-tale signs were obvious beforehand – that David Cameron was always going to become the leader of the Conservative Party, that UKIP would always prosper when the Tories entered office. Those who over-learn from history may be in just as much trouble as those who don’t learn at all.
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