Mary Eberstadt argues in the June/ July edition of Policy Review that contrary to popular opinion, secularism did not lead to smaller families but it was smaller families (and the reduction of major experiences like births which normally make us think of higher purposes) that led to society becoming less religious.
She uses a few examples to highlight the correlation between family size and religiosity and of course a basic rule in statistics is that correlation does equal correlation. In this case she suggests that the direction of causation could go either way – from small families to less religion or form less religion to smaller families. Although she talks about evidence that supports the former hypothesis she doesn’t actually say what that evidence is as far as I can see.
She then goes onto to conclude that if her hypothesis is correct then future trends in the reduction in religiosity are no a full gone conclusion – if family sizes go up in the future. This has happened in the past she says and could happen again (if for example the US provided cheaper education although I always thought higher education mean smaller families!) although she doesn’t acknowledge the critical population crisis the world is facing and that the urgent need for population reduction is being recognised from Rwanda to the UK.