In a Turing Test, a computer tries to pass for human:

A human judge engages in a natural language conversation with one human
and one machine, each emulating human responses. All participants are
separated from one another. If the judge cannot reliably tell the
machine from the human, the machine is said to have passed the test.

In his FiveBooks interview with the Browser, Paul Krugman seems to suggests an analogous test.  According to Krugman, liberals have the ability to simulate conservatives, but conservatives lack the ability to simulate liberals:

[I]f you ask a liberal or a saltwater economist, “What would somebody on
the other side of this divide say here? What would their version of it
be?” A liberal can do that. A liberal can talk coherently about what
the conservative view is because people like me actually do listen. We
don’t think it’s right, but we pay enough attention to see what the
other person is trying to get at. The reverse is not true. You try to
get someone who is fiercely anti-Keynesian to even explain what a
Keynesian economic argument is, they can’t do it. They can’t get it
remotely right. Or if you ask a conservative, “What do liberals want?”
You get this bizarre stuff – for example, that liberals want everybody to ride trains,
because it makes people more susceptible to collectivism. You just have
to look at the realities of the way each side talks and what they know.
One side of the picture is open-minded and sceptical. We have views
that are different, but they’re arrived at through paying attention.
The other side has dogmatic views.

It’s easy to scoff at Krugman’s self-congratulation, but at the meta-level, he’s on to something. Mill states it well: “He who knows only his own side of the case knows little of that.”  If someone can correctly explain a position but continue to disagree with it, that position is less likely to be correct.  And if ability to correctly explain a position leads almost automatically to agreement with it, that position is more likely to be correct.  (See free trade).  It’s not a perfect criterion, of course, especially for highly idiosyncratic views.  But the ability to pass ideological Turing tests – to state opposing views as clearly and persuasively as their proponents – is a genuine symptom of objectivity and wisdom.

There are important caveats.  Don Boudreaux wisely observes that we should compare liberal intellectuals to non-liberal intellectuals, and liberal entertainers to non-liberal entertainers, not say Krugman to Beck.  I’d add that we should compare people in the same field: Rand’s inability to explain Keynesian economics would be no more telling than Krugman’s inability to explain Nozickian political philosophy.  (Of course, if Krugman could correctly explain Nozickian political philosophy, that would be fairly impressive).

With all these caveats in mind, let’s return to Krugman’s empirical claim.  If we did an apples-to-apples comparison, would liberals really excel on ideological Turing tests?

If we limit our sample to Ph.D.s from top-10 social science programs, I don’t see how Krugman could be right.  You can’t get a Ph.D. from Princeton econ without acquiring basic familiarity with market failure arguments and Keynesian macro.  At least you couldn’t when I was a student there in the 90s.  In contrast, it’s easy to get a Ph.D. from Princeton econ without even learning the key differences between conservatism and libertarianism, much less their main arguments.*  And frankly, it shows.  I’ve known many liberal Ph.D.s from top-10 social science programs – and even those who know me best can’t articulate my views well.

Of course, you could dismiss all these claims as swiftly as most non-liberals dismiss Krugman’s.  But the beauty of the notion of the ideological Turing Test is that it’s a test.  We don’t have to idly speculate about how well adherents of various ideologies understand each other.  We can measure the performance of anyone inclined to boast about his superior insight.

How?  Here’s just one approach.  Put me and five random liberal social science Ph.D.s in a chat room.  Let liberal readers ask questions for an hour, then vote on who isn’t really a liberal.  Then put Krugman and five random libertarian social science Ph.D.s in a chat room.  Let libertarian readers ask questions for an hour, then vote on who isn’t really a libertarian.  Simple as that.

My challenge: Nail down the logistics, and I’ll happily bet money that I fool more voters than Krugman.  Indeed, I’ll happily bet that any libertarian with a Ph.D. from a top-10 social science program can fool more voters than Krugman.  We learn his worldview as part of the curriculum.  He learns ours in his spare time – if he chooses to spare it.

Want to prove me wrong?  Set up a rough-and-ready ideological Turing Test.  I’ll take it first.  Then invite Krugman to make me eat my words.

* You might protest that libertarianism is far less prevalent than conservatism.  But that’s only true for the general population, not the world of ideas.  Prominent libertarian economists and philosophers outnumber prominent conservative economists and philosophers.  Can you name a post-1900 conservative economist as well-known as Milton Friedman, or a post-1900 conservative philosopher as well-known as Robert Nozick?