People who don’t believe in God tend to be more intelligent – and this is a fact which has been shown by multiple studies.

But the debate over why atheists might be more intelligent goes back much further, to Greek and Roman times – and it’s not because one belief system is more ‘correct’.

A new scientific paper by Edward Dutton of the Ulster Institute for Social Research in the UK, and Dimitri Van der Linden of the Rotterdam University in the Netherlands suggests an answer.

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The authors suggest that the reason could be explained if religion is considered an instinct – one which intelligence gives people the ability to overcome.

It means that non-religious people may be better problem solvers.