An Evolutionary Explanation for Confirmation Bias

Why do humans reason?  Is it to get at truth or is it for something else?

If you have ever been in an argument with someone, and who hasn’t, then you’ve surely encountered confirmation bias. In fact, you’ve probably been guilty of confirmation bias yourself when arguing (I sure have). Confirmation bias means that you start with a belief or an idea and then magically, using your human reasoning abilities, find arguments that support your belief or idea while ignoring or discounting the arguments against your belief. In other words, you find reasons and arguments to support your beliefs or ideas, but unfairly dismiss those arguments that don’t bode well for your case.

The process of doing this is a form of rationalization.  Evolutionarily speaking, there are more reproductive benefits that come from engaging in sophistry than there are in seeking truth.  That’s right, when it comes to impressing others, is often better to appear right than to actually be right.  Dan Sperber and Hugo Mercier have come up with The Argumentative Theory, which explains why we are well equipped to reason towards truth in some situations, but are doomed in others.