Updated January 10, 2017
Here is an excerpt:
At the core of this research is a very simple idea: When people are reasoning, they tend to think only about a relatively narrow range of possibilities. You are sitting there in a restaurant, trying to decide what to order. Almost immediately, you determine that you are going to get either the chocolate cake or the cheese plate. You then start to consider the merits and drawbacks of each option. "Should I get the chocolate cake? Nah, too many carbs. Better get the cheese plate." One important question about human cognition is how people end up choosing one option over the other in a case like this.
But there is another question here that is even more fundamental — so fundamental that it’s easy to overlook. How did you pick out those two options in the first place? After all, there’s an enormous range of other options that would, at least in principle, have been possible. You could have stormed into the kitchen and started eating directly out of the chef's saucepan. You could have reached under the table and started trying to eat your own shoe. Yet somehow you manage to reject all of these possibilities before the reasoning process even begins. It’s not as though you think, "Should I try to eat my shoe? No, it’s not very tasty, or even edible." Rather, possibilities like this one never even enter your reasoning at all.
This is where the notion of normality plays its most essential role. Of all the zillions of things that might be possible in principle, your mind is able to zero in on just a few specific possibilities, completely ignoring all the others. One aim of recent research has been to figure out how people do this. Though the research itself has been quite complex, the key conclusion is surprisingly straightforward: People show an impressive systematic tendency to completely ignore the possibilities they see as abnormal.
The article is here.