Dr. David Eagleman

I did the calculation and...

figured out that it only took 0.6 of a second to get from the top to the bottom.

And I couldn't figure out why it seemed to have taken so long.

So I think that got me really interested in perception and the machinery by which we view the world and taken in and what is actually real versus what's a construction of the brain.

And that's what I've devoted my career to is figuring out how the brain, which is locked inside the skull, it's about three pounds, how it constructs this model of the world and which things we can take as reality, which things we shouldn't.

One of the things that I started writing about years ago is that I think we're not... I think we often think of ourselves as individuals, meaning not divisible into other things.

But really...

You are a team of rivals.

You've got all these neural networks that have different drives making different suggestions to you.

What's a neural network?

So in the brain, you've got 86 billion cells called neurons, and these are communicating with each other at a blindingly fast rate.

Many of these cells are hooked up in networks.

So they're, you know, this guy's talking to this guy and this guy, and they're all in particular networks, right?

The thing is, you can actually get competing networks.

So, for example, Stephen, if I drop some chocolate chip cookies in front of you, party brain wants to eat it.

It's a good energy source.

Party brain says, don't eat it.

I'll gain weight.

Party says, OK, I'll eat one, but I'll go to the gym tonight.

The point is, you are arguing with yourself.