“We may think we’re being scientists, but we’re actually being lawyers.”

– Jonathan Haidt
Professor of psychology and the University of Virginia

I love this quote. It refers to what happens to everyone when discussing contentious issues. If we have emotion invested in the issue we can get caught up trying to win the discussion (as a lawyer would) rather than trying to resolve it (as an ideal scientist would do).

It’s part of a great article by Chris Mooney in Mother Jones called “The science of why we don’t believe science.” It’s a great, easy read documenting research about how difficult it can be for people to assess evidence for political, cultural or scientific issues objectively.

Here’s a sample of that type of research:

In a classic 1979 experiment (PDF), pro- and anti-death penalty advocates were exposed to descriptions of two fake scientific studies: one supporting and one undermining the notion that capital punishment deters violent crime and, in particular, murder. They were also shown detailed methodological critiques of the fake studies—and in a scientific sense, neither study was stronger than the other. Yet in each case, advocates more heavily criticized the study whose conclusions disagreed with their own, while describing the study that was more ideologically congenial as more “convincing.”

Or another interesting one:

This may help explain a curious pattern Nyhan and his colleagues found when they tried to test the fallacy (PDF) that President Obama is a Muslim. When a nonwhite researcher was administering their study, research subjects were amenable to changing their minds about the president’s religion and updating incorrect views. But when only white researchers were present, GOP survey subjects in particular were more likely to believe the Obama Muslim myth than before. The subjects were using “social desirabililty” to tailor their beliefs (or stated beliefs, anyway) to whoever was listening.

I think this stuff fits nicely into the same category as behavioural economics. Where behavioural economics wonders why we don’t always make perfectly rational economic decisions, this branch of social psychology wonders why we don’t approach evidence in a rational way. Seems people can’t get anything right.