You know something is true—for example, that vaccines are good for children, or that socialism doesn’t work. You’ve done the research, you’ve carefully weighed the arguments against your position and found them wanting, and you’ve diligently formulated your own reasoned case for it.  

And then you try to convince someone else (repeatedly, in some cases), but he or she remains stubbornly opposed.


Well, for Christians, it’s mainly because human reason is fallen, and as a result, men and women are often blind to their own ignorance.

But according to recent science, it’s a function of evolution and humans’ need to adapt.

Pulitzer-Prize-winning author Elizabeth Kolbert outlines some of the science behind the limitations of reason in her article in February’s New Yorker, “Why Facts Don’t Change Our Minds.”

Kolbert begins her article by citing a pair of famous Stanford studies in which students were told to make a judgment based on some information provided to them. It was subsequently revealed to them that the basis for their judgments was completely false, and thus, that their judgments were unwarranted. What did the students then do? They persisted in their judgments and failed to make any revisions!

Scientists have recently argued that this kind of intellectual stubbornness has to do with the evolution of reason itself. According to cognitive scientists Hugo Mercier and Dan Sperber,

“Reason developed not to enable us to solve abstract, logical problems or even to help us draw conclusions from unfamiliar data; rather, it developed to resolve the problems posed by living in collaborative groups.”

Thus, that annoying tendency called “confirmation bias,” where people gravitate toward evidence that seems to confirm their already-held beliefs. According to Mercier and Sperber, confirmation bias…

“… reflects the task that reason evolved to perform, which is to prevent us from getting screwed by the other members of our group. Living in small bands of hunter-gatherers, our ancestors were primarily concerned with their social standing, and with making sure that they weren’t the ones risking their lives on the hunt while others loafed around in the cave. There was little advantage in reasoning clearly, while much was to be gained from winning arguments.”

From a social perspective, I’m not so sure there is much advantage in reasoning clearly today, either. After all, people who strive to be careful in their thinking and broad-minded in their positions are often rather lonely individuals. The herds are much more welcoming of hasty dogmatists. 

And from a realist perspective, if the conclusions of the above studies are sound, I’m not so sure there’s much hope for the expansion and triumph of that mythological concept of “pure reason” anytime in the near future.