Over the last few months, some correspondents have been unsympathetic towards my contentions that nurture, upbringing, schooling and other environmental factors appear to have much less effect on how children develop than might be expected. I accept that this is a radical idea, but it is also one where the evidence is quite conclusive. But perhaps I have been remiss in presenting that evidence.
A few posts ago, I mentioned studies on the Chicago state school system where it was found that there was no direct correlation between an individual’s results and how ‘good’ the school they went to was. As explained in Freakonomics, that is not quite the full story. The system in Chicago is that you can either accept the local school or, if you are unhappy with it, you can enter the lottery. The academics found that children whose parents entered them into the lottery did better than those who just went to the school to which they were originally allocated – even after allowing for the fact that children entered for the lottery might end up at a better school than otherwise. They also found that middle class parents were much more likely to enter their children for the lottery than just accept the allocation. It was a classic case of middle class children doing better wherever they ended up at school.
So was it the middle class upbringing that led to children performing better or the middle class genes? The academics dug deeper and found that there was not a single factor in the children’s upbringing (whether they were read to at bed time, or there were plenty of books in the house etc etc) that correlated to exam results. It looked like it was genetic.
Here’s another example, taken from Steven Pinker’s The Blank Slate. It is uncontroversial that the children brought up by single parents have worse school results, worse outcomes and are more likely to be single parents themselves. Traditionally, this has been assumed to be due to the lack of a father-figure, poverty or the stress involved in living in a broken family. In other words, it is a classic case of how nurture effects the way people turn out. But when you split the figures up between families where the husband has absconded and where he has died, you get different results. Children brought up by widows do not have worse outcomes than in general and are as likely to stay married. Children brought up by divorced or never-married mothers are more likely to be divorced themselves, do less well at school and have lower lifetime outcomes.
How can you explain this? It is certainly not stress. Upsetting as it is for a father to leave home, it is nothing compared to a bereavement. It isn’t poverty either. Widows are not richer than divorcees. The only correlating factor appears to be the parents themselves, in which case the differences must be caused by genes.
This is not just an academic question. All our social and education policies are based on the idea that nurture matters and is something we can change. It is generally agreed that our policies are not working as they should. I would suggest that much of the reason for this is that they are based on an axiom that is untrue.
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