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Hello, today we're looking at a question that in the words of one of our contributors has stalked the 20th century.

Intelligence.

Since the first IQ tests were invented in 1905, the question of what makes

homo sapiens stupid and what makes him clever has often involved

humankind in sterilization, racism, hubris and misery. But are we any closer to understanding what this elusive

quality of intelligence is? The debate still rages as to whether we're born with

it or whether intelligence is something we develop as we grow, and evidence for both seems to pile up almost daily.

Joining me today is the educational psychologist Dr Ken Richardson until recently he was

senior lecturer at the Open University and is the author of Understanding Intelligence

and the Origins of Human Potential and a new book called The Making of Intelligence.

I'm also joined by Professor Michael Ruse of the University of

of Gulf Ontario. He's a philosopher of biology and the author of

Mystery of Mysteries. Is evolution a social construction?

Ken Richardson, how briefly, if that's's possible would you define intelligence? I see

intelligence as the mental abstraction of the complex informational structure in the

spheres of our activity.

Take driving, for example,

your decision to overtake a vehicle in front isn't simply based on the association with your speed of approach to it.

You've got to make decisions based on whether or not

there's traffic coming in the opposite direction and that depends on the

...