Dan Sperber came up with the argumentative theory because he was taking stock of what was happening in the world of psychology at large. A lot of people in psychology were accumulating evidence that the mind, and reasoning in particular, doesn’t work so well. Reasoning produces a lot of mistakes. We are not very good in statistics, and we can’t understand very basic logical problems.
We do all these irrational things, and despite mounting results, people are not really changing their basic assumption. They are not challenging the basic idea that reasoning is for individual purposes. The premise is that reasoning should help us make better decisions, get at better beliefs. And if you start from this premise, then it follows that reasoning should help us deal with logical problems and it should help us understand statistics. But reasoning doesn’t do all these things, or it does all these things very, very poorly.
But for some reason, psychologists are unable to challenge this basic premise that reasoning really is supposed to help us. And that’s why Dan Sperber came up with the idea that reasoning doesn’t have this function of helping us get better beliefs and make better decisions. Instead, reasoning is for argumentation. Dan’s basic idea is that the function of reasoning, the reason it evolved, is to help us convince other people and to evaluate their arguments.
Here we have a radically different idea that stands apart from the common wisdom in psychology, cognitive science, and even in philosophy. In Western thought, for at least the last couple hundred years, people have thought that reasoning was purely for individual reasons. But Dan challenged this idea and said that it was a purely social phenomenon and that the goal was argumentative, the goal was to convince others and to be careful when others try to convince us.
And the beauty of this theory is that not only is it more evolutionarily plausible, but it also accounts for a wide range of data in psychology. Maybe the most salient of phenomena that the argumentative theory explains is the confirmation bias.
Psychologists have shown that people have a very, very strong, robust confirmation bias. What this means is that when they have an idea, and they start to reason about that idea, they are going to mostly find arguments for their own idea. They’re going to come up with reasons why they’re right, they’re going to come up with justifications for their decisions. They’re not going to challenge themselves.
And the problem with the confirmation bias is that it leads people to make very bad decisions and to arrive at crazy beliefs. And it’s weird, when you think of it, that humans should be endowed with a confirmation bias. If the goal of reasoning were to help us arrive at better beliefs and make better decisions, then there should be no bias. The confirmation bias should really not exist at all. We have a very strong conflict here between the observations of empirical psychologists on the one hand and our assumption about reasoning on the other.
But if you take the point of view of the argumentative theory, having a confirmation bias makes complete sense. When you’re trying to convince someone, you don’t want to find arguments for the other side, you want to find arguments for your side. And that’s what the confirmation bias helps you do.
The idea here is that the confirmation bias is not a flaw of reasoning, it’s actually a feature. It is something that is built into reasoning; not because reasoning is flawed or because people are stupid, but because actually people are very good at reasoning — but they’re very good at reasoning for arguing. Not only does the argumentative theory explain the bias, it can also give us ideas about how to escape the bad consequences of the confirmation bias.