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.

That would explain recent survey data which supports the stance that intelligence seems to be negatively associated with being religious, the authors write.

‘If religion is an evolved domain then it is an instinct, and intelligence – in rationally solving problems – can be understood as involving overcoming instinct and being intellectually curious and thus open to non-instinctive possibilities,’ Dutton writs.

Dutton argues that being intelligent helps people to rise above their instincts during stressful times – a useful skill.

‘If religion is indeed an evolved domain – an instinct – then it will become heightened at times of stress, when people are inclined to act instinctively, and there is clear evidence for this,’ says Dutton ‘It also means that intelligence allows us to able to pause and reason through the situation and the possible consequences of our actions.’