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Hello, the question of consciousness, our sense of self and how we're able to imagine things

when they're not there are problems that have engaged the great minds of philosophy for

thousands of years.

Consciousness has been linked to language, has been married to the mind,

and divorced from the body. It's been denied to animals, opposed to the subconscious and declared

irreducible. But it still seems to defy definition, and the debate rages on as to why we evolved it at all.

Perhaps science will finally provide the answer.

Today I'm joined by the Nobel Prize winner, the Neuroscientist Gerald Adelman, who claims his new book, Consciousness How Matter Becomes Imagination

is the first ever explanation based upon scientific experiment.

Also here is Igor Alexander, who's been studying artificial consciousness for more than 30 years.

He's professor of neural engineering systems at Imperial College, and author of a new book also called

How to Build a Mind.

And representing the world of philosophy, Professor Margaret Bowden an expert in

cognitive science at the University of Sussex.

General Adelman, your work in neuroscience is focused on what you've called neural Darwinism. You've said you wanted to

complete Darwin's program. Could you elaborate that first place? Well yes I

adopted that term because I think Darwin made the most extraordinary advance in so-called

population thinking, the idea that categories and species of animals come out of differences in

populations of individuals under natural selection or competitive constraint.

And my personal belief is that since the brain doesn't appear, had a

...