There is definitely a meme in the progressive blogosphere that conservatives and liberals think differently. People try to be polite, but I don’t think I’m the only person who perceives it to be really about the hypothesis that conservatives are not capable of rational thought.
One way of putting this is that “The Republican Brain” may have joined “What’s the Matter with Kansas” and “The Emerging Democratic Majority” and everything Richard Perlstein ever wrote on the list of books (which I haven’t read) which every progressive much read.
Also a favorite topic of mine is public it’s not a matter of opinion polling. Occasionally pollsters ask about verifiable facts (famously what fraction of the US Federal budget goes to foreign aid) and find the most remarkable beliefs.
There is some evidence that Conservatives’ beliefs are further from reality than liberals’ beliefs.
(non irony alert)
I think the evidence which I discuss below is not convincing, because the studies may be skewed, because the facts have a liberal bias.
In the USA the winter of 2012 was extraordinarily warm. Chris Mooney himself links to a study which notes that Liberals are more likely than conservatives to recall it that way.
Bill Gardner described a study (pdf warning) by Wendy Gross, Tobias Stark, Jon Krosnick, Jash Pasek, Gaurav Soods, Trevor Tompson, Jenifer Agiesta and Dennis Junius which shows the more people know about the Affordable care act, the more likely they are to favor it.
Fox News viewers didn’t know the facts about the US invasion of Iraq.
OK but I wasn’t joking about the liberal bias of the facts. The researchers who study the phenomenon have to choose a set of facts before testing knowledge of the facts. In the case of the warm 2012 Winter, the fact clearly fit the anthropogenic global warming hypothesis. A crafty conservative social scientist, could argue that liberals don’t accept the facts by asking if 1998 or 2012 were hotter (1998 is the base year for all conservacalculations of global warming, since it was extraordinarily hot).
Also in the case of the ACA the correct answers to the questions of fact were facts which tended to suppor the case for the ACA (at least the ones I looked at were).
The data which I have seen do not reject the hypothesis that
1) people’s beliefs of fact are influenced by their general ideology
2) this is equally true of liberals and conservatives
3) The whole body of evidence gives balanced support for liberalism and conservatism
4) the particular facts selected for the studies support liberal conclusions and so liberals are more likely to believe them.
I am very confident that part 3 of this hypothesis is false. But the recent research to which I linked, doesn’t test, let alone reject, the joint hypothesis 1-4.