Quick note before we get started, this episode includes a racial epithet and discussions about pornography.

This is Hidden Brain, I'm Shankar Vedantam.

Maps are good representations, not just of the world we live in, but of how we think about the world we live in.

Over the centuries, our maps have emphasized the places we find important.

They show the limits of our knowledge and the scope of our ambitions.

700 years ago, Europeans were completely unaware of the existence of North America.

Fast forward to the 1970s.

Scientists can tell you in detail what the surface of the moon is like.

Today, we're charting out maps of a different sort.

Maps of our minds.

Mines.

Maps of our minds.

There is in one cartographer designing these modern maps, we all are, and the maps are constantly changing.

We start today's show with a personal question.

Have you ever Googled something that you would never dream of saying out loud to another human being?

When we have a question about something embarrassing or deeply personal, many of us today don't turn to a parent or to a friend,

but to our computers.

Because there's just some things you just can't ask a real person in real life and you need to ask Google.

Because it's completely anonymous and there are no judgments attached.

Google knows everything.

I agree to it.

Every time we type into a search box, we reveal something about ourselves.

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