Asks Ezra: "If John Rawls had never existed, it's very clear that American political philosophy would look very different. But is it actually clear that American politics would look even a little bit changed?" Probably not, I think. The lesser reason is that his political philosophy actually didn't have very distinctive consequences relative to the American political environment. The greater reason is that we're in a political climate where intellectuals don't have much influence.
I was teaching two weeks of Rawls in my political philosophy seminar this semester, and on rereading it struck me how similar the practical consequences of his views are to the utilitarian views he displaced on the American political philosophy scene. Rawls' difference principle, which basically says that social distributions of goods are better insofar as the people on the bottom are better off, isn't a theory about how happiness should be distributed. It's a view about how social primary goods, like wealth and opportunity, should be distributed. Given the diminishing marginal utility of such goods, a utilitarian will be most concerned with helping the people with the least. There are still going to be differences between the distribution I want and the distribution Rawls wants. But given the existing distribution of goods in American society, Rawls and I are going to be pulling for basically the same political proposals.
Of course, the deeper you get into the theory, the bigger my differences with Rawls get. I think his justifications for why people in the original position would choose the difference principle aren't very good, and he'd do better to just appeal to diminishing marginal utility. His point about the separateness of persons and how you can't make up for harming one person by benefitting another -- his key objection to utilitarianism -- isn't respected by his own theory, which allows you to trade off harms and benefits as long as you do it within classes of people. At least as it's written, the methodology of reflective equilibrium doesn't allow for the sorts of debunking moves that my defense of utilitarianism depends on. But inside baseball stuff like that isn't going to have a popular impact.
(A relevant boast: we utilitarians may be almost as dead as the logical positivists on the US philosophy scene, but which philosopher does Nicholas Kristof sympathetically cover in a very nice column? Peter Singer, taking the side of animals against the meat industry. This is what happens when you have distinctive and striking commitments that touch diverse and sensitive aspects of human life. Which isn't an objection to Rawls -- it's just an explanation for why he wasn't as splashy.)
But the bigger reason why Rawls didn't make a big splash is just that the forces governing American politics at present don't put any premium on intellectual opinion, or show any interest in mainstreaming intellectual debate. The same circumstances that make it possible for George W. Bush to beat Al Gore in 2000 and Sarah Palin to be chosen as a vice-presidential candidate in 2008 prevent any current political philosopher from making an impact. If I saw a bunch of American TV pundits eagerly speculating about which candidate would win the intellectual vote, I'd make sure not to drive or operate heavy machinery in the next twelve hours. Rawls may have a nifty argument that you're not entitled to the things you get in the free market, since those things are really just products of other things that you didn't earn any more than a prince earned his hereditary title. But even though that argument was able to keep the young Texans in my Business Ethics section in their seats, trying to figure a way out, several minutes after the bell rang, it's not the sort of thing that you're going to see on cable TV anytime soon.
Being a philosophy professor who's interested in politics, you might expect me to be rather unhappy about this state of affairs. And, yeah! I'd really like it to change. The funny thing is that I've grown up so fully within this political environment that I've come to accept its constraints. My plans for having political impact generally stand apart from my research. It's kind of a weird thing to say now, just as I'm finally starting to write up my big argument for utilitarianism, the theory that stands at the foundation of my political views. But as awesome as I think the argument is, and as dramatic as its consequences are for how the world should be, I don't really think about it affecting the way anybody outside philosophy thinks about anything.
My teaching might inspire a few kids to do good things or turn their energies in socially beneficial directions, though I'm not under any illusions about my ability in that regard. I can give away a big chunk of my salary to people and causes that will make the world a better place. I can do the sort of thing that all of us bloggers do (thanks to all you for reading!) And hey, maybe the American political environment will emerge from the anti-intellectual shadow of whatever it was that made this happen. But until I see that happening, I'm not expecting to write any journal articles that change the world.