Does intelligence or schooling matter? These are two questions raised by the recent furore over Toby Young's now-rejected appointment to the OfS. Good people have fiercely opposed Young's "progressive eugenics", and rightly so. But I fear they haven't sufficiently acknowledged the germs of truth in what he says.

One such truth is that IQ is heritable. One survey has found (pdf) that:

Correlations of IQ between parents and offspring range from 0.42 to 0.72.

These aren't the words of right-wing nutjobs. They're those of Sam Bowles and Herb Gintis, two of the greatest leftist economists.

The question is: so what? It's here that people like Young go wrong.

For one thing, as Bowles and Gintis show, these correlations explain only a minuscule fraction of the intergenerational transmission of wealth, income and status. One reason for this is that plenty of things other than IQ explain earnings such as effort and social skills, which might or might not be inherited. Another reason, of course, is that rich parents don't only give their children higher IQs: they also give them role models and networks.

This, though, is a minor point. What's more significant for me is that higher IQ does not justify inequality. Young writes:

All things being equal, a country's economy will grow faster, its public services will be run better, its politicians will make smarter decisions, diseases are more likely to be eradicated, if the people at the top possess the most cognitive ability.

That phrase "all things being equal" is doing too much work. Cognitive ability is no assurance of better policy. In fact, it's possible that high IQ is a drawback as it might make one less able to get people on your side and more willing to pursue tricksy complicated policies than simpler ones. We'd be better off today if we'd had basic first-year undergraduate macroeconomic policy implemented by dullards rather than austerity implemented by cleverer people*. And many of us would prefer a simple basic income to Gordon Brown's complex tax credits.

Leaders -in politics or business - must justify themselves by their day-to-day decisions and not by their score on some abstract IQ test. Intelligence is context-specific: the world is full of people who are brilliant in their fields but daft outside.

Above all, though, differences in IQ do nothing to justify inequalities of income, status or power. In any unjust hierarchical society men with high IQs might well do better than others; you needed cognitive skills to climb the USSR's bureaucracy or to pass the civil service exam of medieval China. Maybe the correlation between IQ and status was higher in the USSR than it is in western societies today. But that does nothing to defend the USSR's social structure.

Con-men are probably smarter than their marks. But that doesn't justify fraud.

There's something else Young says that's plausible:

it is naïve to think schools can do much to ameliorate the effects of inequality. I don't just mean socio-economic inequality; I also mean differences in intelligence.

Here, though, is another great leftist economist, John Roemer:

increased school spending is associated with, at best, rather small gains in adult earnings.

But what political ideas flow from this? Yes, this rules out "blank slate" romantic notions that every child is a potential Einstein if only they get sufficiently good education. And it tells us that equality of opportunity is a utopian sham.

But many of us lefties have never much believed in those ideas.

In fact, all this evidence actually strengthens one sort of leftism. To the extent that some people are poor because they've lost in the genetic lottery then their poverty is due to circumstances beyond their control. And equally, the success of the rich is beyond their control. Luck egalitarianism then mandates that these inequalities be eliminated.

To luck egalitarians, the more true it is that inequalities are due to genetics rather than to people's own efforts, the stronger is the case for redistribution. In this sense, a belief in the importance of genetics actually strengthens some leftists' positions.

The issue here is the validity or not of luck egalitarianism, not of genetics.

My point here is a simple one. Maybe it is the case that some people, by virtue of their genes, have more chance than others of being at the bottom of the social heap**. How unpleasant life is at the bottom of that heap is, however, a political choice.

* I leave aside the question of Osborne and Cameron's IQs as utterly uninteresting.

** This is not to say they are destined to so be: the correlations are less than unity.