This is Hidden Brain. I'm Shankar Vedantam.

I have a question for you. How well do you know yourself?

Chances are you'll tell me you know yourself very well.

All of us like to believe this.

We feel like we know ourselves better than anyone else does.

Every day we make choices based on this knowledge we have of ourselves.

We decide how to spend our money, who to vote for, where to go for dinner, based on what

we know of our predilections and preferences.

But our knowledge of ourselves is not always accurate.

A host of biases and self-deceptions keep us from seeing ourselves clearly.

When you ask people how smart they are, or how ethical they are, or how good-looking they are, for example,

majorities say they are above average, which of course is mathematically impossible.

But it isn't just about vanity. How many times have you gone to a restaurant you've been to

before and ordered the same dish you ordered last time only to remember after you started eating

it that you didn't like it the last time? Or think about your last romantic entanglement that ended in disaster.

By the time it ended, did you wonder how your past self could have gotten involved with someone so unsuitable?

Over the last few decades, researchers in a variety of disciplines have discovered there is a

much better way to understand people than to ask them questions.

When you ask people what books they like to read, people will tell you about the novels

and biographies they think they ought to like.

If you ask them what movies they want to watch, they will tell you about the movies they

aspirationally want to watch.

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