This is made in philosophy bites with me David Edmonds and me Nigel Warberton.

Philosophy bites is available at W.

Philosophy bites.com. Philosophy bites is made in association with the Institute of Philosophy.

We're about to introduce you to Mary and a red tomato.

Mary's an imaginary person living in bizarre circumstances, of which more are non.

Her creator is a distinguished Australian philosopher.

When Frank Jackson dreamed up Mary, it was to use as an intellectual weapon against a

physicalist or materialist, against those who believe

that the only things that exist in the world are physical.

Professor Jackson used to believe that Mary believed there were mental states distinct from

physical states and that these mental states

were epiphenominal, i.e. they had no influence on physical states. But back to Mary and what she knew about

that tomato. Frank Jackson, welcome to Philosophy Bites.

Thank you very much, natural.

We're going to talk about a very famous thought experiment,

what Mary knew, and you're responsible for that thought experiment.

Could you just begin by telling us how you came up with it?

There's a bit of history. I used to be at Monash and that was back in the days

when nearly all philosophers of mind were materialists.

And the psychology department discovered that there was a dualist in the philosophy department.

And they said, let's ask this dualist across to give us a lunchtime talk and explain how you could possibly

not be a materialist.

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