Britons think 22 per cent of the population will be Muslim by 2020. The real figure is 7 per cent

The best estimate is that around 7 per cent of the UK population will be Muslim by 2020. That’s pretty fast growth, up from nearly 5 per cent in 2016, due mainly to migration and higher fertility in the Muslim population. But the average guess from a representative sample of Britons was that 22 per cent of us will be Muslim by 2020—one in five. That’s not just a bit out, it’s thrice the reality.

What people get spectacularly wrong is often revealing. We suffer from “emotional innumeracy,” overestimating that which we worry about—and letting slip an unconscious signal of alarm. Estimates get particularly skewed when the information people see is slanted, as is the case with what the majority reads and sees about Muslims. Studies in the UK and US have shown that up to 90 per cent of media coverage of Muslims is negative. Our brains process negative information differently, storing it more readily. This is an evolutionary trait—staying alert to threats was what kept us alive in our pre-historic past.

But Britons—both Muslims and non-Muslims—can take some solace that their country suffers from less distortion than France. Its secular suspicion of all religion has been visited more intensely on Muslim communities in the wake of recent jihadi attacks. And the French guess that 40 per cent of their population will be Muslim by 2020; the best estimate is around 8 per cent. That 40 per cent guess would be the equivalent of every adult French man being Muslim. Anyone with any command of numbers should be able to see this is absurd—but such is the ability of bad news and suspicion to warp the mind.

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