Earlier in the week I interviewed Arthur Brooks, head of the AEI, about his new book, "The Road to Freedom: How to Win the Fight for Free Enterprise". I recommend it. Brooks's main point is that conservatives ought to stop ignoring fairness as a criterion for judging public policy. More often than not, he says, they cede that argument to liberals, resting their case on the productivity of market forces and inviting the charge that they are heartless. That's not good enough, Brooks says. People are right to demand fairness. Conservatives have to show that they can deliver.

Of course, everything depends on what you mean by "fair". The book therefore pivots on the distinction Brooks draws between egalitarian fairness and meritocratic fairness.

To dismiss fairness is like dismissing love: a difficult phenomenon to identify quantitatively, but a central facet of life and hugely important to nearly everybody.

The real question os not whether fairness matters--it does--but which definition is correct for public policy. Is it equal outcomes, rewarding merit, or something in between?

Unfortunately, he doesn't take what I think is the right answer--something in between--very seriously. Instead he argues as though "equal outcomes" and "rewarding merit" are the only choices. "Equal outcomes" is plainly a terrible goal, not least because it's unattainable. And it so happens that Americans, since they founded their nation, have strongly preferred rewarding merit over pure redistribution. It's bred in the bone. So that's about that, according to Brooks: Merit-fairness is correct and equal-outcome-fairness is just plain wrong.

I disagree, but let's move on. Unlike many conservatives, Brooks immediately concedes that meritocratic fairness is a bit more complicated than you might think, because it has to take account of disparities in opportunity. This is a much bigger concession than I think he realizes. At any rate, he says, it implies the following test:

If individual opportunity is a sham--if the system is fixed and some people get the breaks only by virtue of luck or birth or skin color--then inequality isn't fair at all... But if America is an opportunity society--if, in fact, people have the chance to work harder, get more education and innovate--then rewarding merit is fair, and for some people to make more money is good and just.

The real question, then, is whether America is an opportunity society. If it is, then inequality is fair. If it isn't, then inequality isn't fair.

According to the evidence, the United States is an opportunity society, even if an imperfect one.

Brooks is a smart, witty and engaging writer, and it's refreshing to see a conservative cast the argument for free enterprise in these terms. His emphasis on opportunity is right, he asks smart questions, and he suggests a great many policies that intelligent liberals and conservatives ought to be able to agree on. That's why I urge you to read the book. But his answer to the question he correctly says is crucial--is America an opportunity society?--is cursory and not at all convincing.

Again, the problem is the excluded middle. The United States is "an opportunity society, even if an imperfect one". Yes, but how imperfect? The question is not whether America is an opportunity society, but to what degree. To be sure, perfect equality of opportunity is no more attainable than perfect equality of outcomes. A society in which some parents are rich and well-connected and others are not is a society of less-than-equal opportunity for their children. No society can eliminate this unfairness, and no society that values liberty would wish to try--but a just society can still strive to reduce it.

Brooks argues that America is a land of opportunity because children of poor parents move up and children of rich parents move down. That's true, but the evidence is pretty clear that the US does not perform very well on this measure of mobility compared with other countries. Brooks might disagree with those findings but it's a serious weakness of the book that he doesn't even address them.

Notes from the Aspen Ideas Festival -- See full coverage

This week at the Aspen Ideas Festival I've been stalking Robert Putnam as he's appeared at various sessions. He's described work in progress that strongly supports two main findings. First, that racial disparities in the United States, controlling for socio-economic class, are narrowing. In other words, the lives of prosperous non-whites are looking more like those of successful whites, and the lives of low-income whites are looking more like the lives of poor non-whites. Second, that class disparities in the United States, controlling for race, are widening dramatically. The prosperous and the poor, regardless of race, are living in increasingly separate worlds.

(Yes. Aspen. Separate worlds. I know.)

The standard data on intergenerational social mobility (like the ones mentioned in my Atlantic article) are backward looking, as Putnam emphasized. Those studies ask how well today's adults are doing compared to their parents. This tells you something about equality of opportunity when today's adults were children. Putnam's research is an effort to look forward. It sifts data about children and teenagers today. He believes America's earlier middling-at-best performance as an opportunity society is deteriorating very rapidly. The outlook he describes is alarming.

So far as I know, Brooks and Putnam didn't get together at the meeting. It's a conversation I'd have liked to listen to.