I'm William Brangham and this is Horizons.

All of us experience consciousness.

We have thoughts and feelings and we're aware of those acting upon us.

It's the hidden internal lens through which we view the world.

But why do we have this power?

And are we the only ones to do?

Coming up next.

Welcome to Horizons from PBS News. Take a moment right now and think about what you're feeling. What are you thinking about right now? Does me asking this feel awkward, irritating? Did your mind just drift

to something that happened earlier? Are you thinking about your next meal? Whatever you are

feeling right now, that sensation, that voice inside your head is partly what we call

consciousness. This awareness of our internal selves has long been held up as one of the defining

aspects of being human. But why do we do this? What purpose does it serve? And where does

consciousness actually live inside our brains or bodies?

These are some of the questions that Michael Pollan is trying to answer in his new book,

A World Appears, a Journey into Consciousness.

Pauline is one of the great science writers of our era.

He has written numerous books about food and our food system,

including The Omnivores Dilemma and In Defensive Food, as well as several books about the in our food system, including the omnivore's dilemma and in defense of food,

as well as several books about the science of mind-altering substances, including how to change

your mind, which is about psychedelics. Michael Pollan, such a pleasure to have you on the program.

Thank you, William. Very good to be here. So I gave a, I took a stab at a definition.

That was pretty good, I thought. Really? Yeah, that's high praise. I love that. What would you add to that about this idea?

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