People have often speculated on the idea of a "religion gene" or "God gene", which predisposes towards belief in a deity. The specific idea in the link here appears to be twaddle, but I am intrigued by the idea that a bunch of genes code for religious inclinations. I'm assuming that in the same way white cats are predisposed to congenital deafness, so a bunch of religion genes would also go along with physical attractiveness and general charisma. And a religion gene makes good evolutionary sense to me - a belief in meaning, purpose, and Someone to watch over you is going to make you stick it out, and maybe even propagate the old genestock, in trying times when your average atheist might decide it's not really worth it.
And I wonder - and it's only a wonder - whether this gives us a clue as to why America has remained a much more religious place than Europe, even though they rigidly separate Church and State. Whereas in Scandinavia, the link between Lutheranism and State means it's compulsory for everybody to be gloomy.
See, what do we know about the early settlers of the US of A? Along with a number of what are called economic migrants, there was a stonking number of people who moved over there for religious purposes. The Pilgrim Fathers (who swiftly had to organise another ship for the Pilgrim Mothers after they realised the awful mistake they'd made if they were to form a viable ongoing colony) were mostly Dissenters. Then alongside the Puritans, there were Quakers looking for a quiet life, and assorted other people who hoped they could either avoid persecution, or impose persecution on others, in the New World.
So by the 19th Century, Europe had accidentally shipped its most religious people (because they were prepared to embrace their unpopular faiths to the point of persecution and emigration) and left behind the people who were happy with the status quo.
Which means, if the theory is right, that it's no wonder America is more religious than Europe. They're coded that way.
Now all we have to do is work out which genes they are, compare descendants of 18th Century English and Dutch immigrants in the US to descendants of people who just stayed where they were - and my theory will be complete.
Who needs sociology of religion when you've got wild theories and no way of testing them?