Heads in the sand: Most of us would prefer not to know whether bad things are going to happen

Humans are infovores, hungry to discover, and nothing holds more fascination than the future. Once we looked for answers through divination, now science can forecast significant events such as the onset of certain hereditary diseases. But the fact that some people choose not to know – even when information is accessible and has a bearing on their lives – has encouraged scientists, including Gerd Gigerenzer and Rocio Garcia-Retamero, to try to map out the limits of our appetite for knowledge. Their recent study in Psychological Review suggests that it is a fear of what we might discover – and wishing that we'd never known – that often drives us to deliberate ignorance.

Gigerenzer, Director of the Max Planck Institute for Human Development, and Garcia-Retamero at the University of Granada, asked nationally representative samples of participants in Germany and Spain whether they would be willing to know the date or cause of their own or their partner's death; whether their marriage would end in divorce; as well as information relating to positive future events like knowing the gender of their unborn child, or what was in store for them under the Christmas wrapping paper.

Whereas previous research with people at heightened risk of specific diseases found rates of deliberate ignorance of between 10 and 30 per cent, the rates here were far higher. Close to 90 per cent of participants said they'd prefer not to know about future negative events (this tended to generalise: a person who didn't want to know about one negative outcome usually said they didn't want to know about any others). Rates of deliberate ignorance were also high for positive events, but more variable – only a third of participants said they did not want to know their child's gender, for instance, compared with three-quarters preferring not to know the outcome of a football match they were watching. So wilful ignorance is commonplace, but what's driving it?

Gigerenzer and Garcia-Retamero's suspicion is that it's about anticipated regret: people's fear that they may regret hearing what's going to happen; after all, you can't "unknow" an unwelcome fact. People susceptible to fearing regret also tend to be risk-averse: taking risks often involves seeing the repercussions of your decision, whereas ducking a gamble simply leaves you in the dark – you'll never know what might have been.

To test whether anticipated regret was driving deliberate ignorance, Gigerenzer and Garcia-Retamero asked their participants to complete classic measures of risk aversion, like choosing between the option of different-sized cash sums now versus a 50 per cent chance to win 100 Euros, with a preference for guaranteed lower sums corresponding to more risk aversion. Supporting their explanation, the researchers found that the participants who'd been keener to stay in deliberate ignorance were also more risk averse. This was true for positive events too, where the regret is related to the possibility of spoiling enjoyable suspense – such as asking to know the football results because the game seems lifeless but then discovering that it turned into a 3-2 nailbiter.

Also consistent with the anticipated regret hypothesis was the finding that participants were more in favour of ignorance when events were imminent. So 13 per cent of under-35s said they would want to know about the date their partner would die, for example, but only 8 per cent of over-50s (similarly 54 per cent of the younger group said they'd want to know about life after death compared with 46 per cent of the older group).

This seems surprising, because information about an imminent outcome is usually considered more relevant, and we tend to think of the young as uninterested in the future and living for today. But if it is regret that's driving things, it makes more sense: a youngster discovering that they will die in their 60s, not the more typical 70s, is unlikely to be devastated by the bad news, but for a 60-year-old, this is too ugly a fact to risk knowing. The researchers also found that participants who bought more insurance policies – a real-world measure of risk avoidance – were also slightly more likely to choose deliberate ignorance for future events.

From a purely rational perspective, it seems surprising that so many people shy away from potentially useful information. Knowing the timing of your future demise could shape how you save for old age, for example, while learning whether an infinite existence lies beyond death would likely shape how you approach this life. But it seems many of us prefer ignorance, driven by the fear that we might regret discovering something better left unknown.