Terry Gross

Would that be a good thing or not?

The book ends with Palin in a cave, sent there by a Buddhist teacher who founded a Zen monastery and wanted Palin to explore the idea of consciousness in a cave and experience how consciousness can change by meditating all alone in a remote area for an extended period of time.

He's a long-time meditator, but this extreme version was something new.

Pollan has kept up with new developments in psychedelics.

He co-founded the University of California Berkeley Center for the Science of Psychedelics, which, among other things, publishes a newsletter about the latest research into the use of psychedelics in therapeutic settings and the latest laws that are loosening or restricting the ability to conduct such research.

Pollan is also known for his writing about food and plants.

His books include The Omnivore's Dilemma, The Botany of Desire, Cooked, and This is Your Mind on Plants.

Michael Pollan, welcome back to Fresh Air.

So which came first, wanting to explore consciousness or wanting to explore psychedelics?

Because you've written two or three very interconnected books.

Well, scientists can't even agree.

The scientists that are studying consciousness can't even agree on what we mean by the word consciousness.

Is there a definition you prefer?

The qualities we now think of as consciousness, you say those used to be attributed to the soul, and the soul was the territory of the priests.

So can you talk about that a little bit?

There's one thing I think that priests and scientists have in common when it comes to either the soul or consciousness.

Priests, I think, would say, well, we don't know exactly what the soul is, but God works in mysterious ways.

And scientists would say, we're gathering evidence about what consciousness is, but there are only current hypotheses.

We don't know for sure.

So there's mystery no matter how you look at it.