To take up another older issue, I had some brief thoughts on the back and forth between Tyler Cowen and Krugman regarding, well, I guess, whether it's more effective to convince people by being nice or by taking the gloves off and slugging it out. Cowen describes the most convincing case as being one that seeks to make the best argument from the opposing side as well as one's own. He goes on to say, "uch an essay would stand a far greater chance of influencing me, or other serious readers, or for that matter President Obama."
Such an argument is convincing up until he mentions President Obama. This debate reminds me a great deal of a quote often attributed to Roosevelt, "you've convinced me, now make me do it."
This is the crux of the problem. Cowen is undoubtedly right that his method is the best way to convince a well informed, serious readership. This stance is widely held in academia, I'd say this is the ideal.
However, this stance is also why outlets of questionable veracity, such as Heritage, dominate the headlines, House Budget Committee reports, and most policy debates. Very few people, even people in decision making positions, can really be classified as serious readers. When I first decided to start studying politics, I asked some people I knew who were in government in Washington what to read. The books recommended to me were generally fairly basic, the ones that weren't were notable for how detail oriented they were, not for the depth of their arguments.
In short, I am very sceptical that the Humean approach has any impact on policy whatsoever. It is certainly the ideal type for discussion in the Academy and is the best way to convince people there. However, if there ever was a transmission belt for ideas from the Academy to policy making circles it largely broke down decades ago. Nonsense like the culture of dependency arguments I rail against dominates over good research. In this environment, it is necessary to pay attention to how politicians and the think tanks they listen to frame their arguments, not what works in elite academic circles.
Now, even given this distinction, I think there is a good argument to be made that Krugman doesn't play this game all that well either. While he likely helped inform some of the arguments made by the Occupy Wall Street protests, I don't see much evidence that Krugman has had a large influence on actual US policy. While this may or may not be due to his skill at this game, it may be that the system is not easily moved by arguments made by individuals no matter how well they play it, Cowen's approach seems to me one that would reduce Krugman's influence from negligible to nonexistent. Presenting both sides as strongly as possible simply isn't how you convince people, it works only with people that have been highly educated to respect this particular form of argumentation. It certainly isn't how you win an argument in a meeting, around the dinner table, or in a bar. But if you want to influence policy, you need to be able to change the grounds for argument in those very places, not in polite company.
The critical thing is about making policy makers do something, and to do this you need to win the argument in a bar, not in the faculty club.
(Looking at Cowen's list of influential intellectuals, I am also struck by how his list doesn't exactly match with people noted for their polite use of the Humean method. Milton Friedman was pretty forceful about his views. Charles Murray is also an interesting example, he influenced policy despite being pretty much universally regarded as wrong by the academic community. His interpretations just don't stand up to scrutiny. He was also quite vicious to the opposing viewpoint, though unlike Krugman his dismissal of other views was presented politely, if not accurately. He didn't give them a fair shake however, he misrepresented them in ways that are similar to what Ryan does by presenting a choice between opportunity and equal outcomes. False choices, not real choices, that don't actually communicate what anyone is saying. As any grade school kid knows, lying by omission is just as bad as lying by commission. But it's tempting, because it seems to work in practice. Well enough to get the author of The Bell Curve onto a respected economist's most influential list anyway. With real policy alterations to back up his place on it.)