The Origin Of Reason

"If we think that we have reasons for what we believe, that is often a mistake." Prof Daniel Kahneman, Princeton University

We can all reason from our childhood onwards - but how? When we think about how we came up with the reasoning of justifying something. We don’t go very far because we have no definite explanation. We arrive at reason from an idea when we want to justify the idea and think that its correct. We don't rely on the laws of logic or probability - we reason by thinking about what's possible, we reason by seeing what is common to the possibilities. 

In an article at Edge.org, there's a great conversation with Mercier, now a post-doc at Penn. Mercier begins by explaining how the argumentative theory of human reason can explain 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.

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. 

The meaning of reason is logical defense. But that’s more of why we reason, the other question is how we reason. It could be because we all have some form of pre-mandated mindset about something and the next time we come to the same situation without knowing it, we conclude to the reason we have all ready justified for ourselves. For example when we go online and we want to shop for some green tea, if we don’t know what brand and what type of green tea we want we start comparing different types of teas with the prices and reviews about the brand from the people who’ve already bought the product. Even though we have no experience in buying green tea we find ourself some form of reason to believe that whatever we’ve selected is the best. Now the next time when we go to a supermarket to buy the green tea we already have the reason in us to decide what to look for. If someone points out that we should take something else we try to come up with all kinds of reason, why the product I’ve selected is the best. In the act we try to persuade other people that what we believe is true.