In April and May of 2013, Yale Law professor Dan Kahan — working with coauthors Ellen Peters, Erica Cantrell Dawson, and Paul Slovic — set out to test a question that continuously puzzles scientists: why isn’t good evidence more effective in resolving political debates? For instance, why doesn’t the mounting proof that climate change is a real threat persuade more skeptics?
The leading theory, Kahan and his coauthors wrote, is the Science Comprehension Thesis, which says the problem is that the public doesn’t know enough about science to judge the debate. It’s a version of the More Information Hypothesis: a smarter, better educated citizenry wouldn’t have all these problems reading the science and accepting its clear conclusion on climate change.
But Kahan and his team had an alternative hypothesis. Perhaps people aren’t held back by a lack of knowledge. After all, they don’t typically doubt the findings of oceanographers or the existence of other galaxies. Perhaps there are some kinds of debates where people don’t want to find the right answer so much as they want to win the argument. Perhaps humans reason for purposes other than finding the truth — purposes like increasing their standing in their community, or ensuring they don’t piss off the leaders of their tribe. If this hypothesis proved true, then a smarter, better-educated citizenry wouldn’t put an end to these disagreements. It would just mean the participants are better equipped to argue for their own side.