How is it that we learn to speak and think in language so easily? Philosophers have argued about whether or not we have innate ideas. Whether we are born knowing things, as Plato believed, or rather, as John Locke and other empiricists argued, the mind is a blank slate on which experience writes. Noam Chomsky, gave a twist to this debate in the 1960s.

Narrated by Gillan Anderson. Scripted by Nigel Warburton.

From the BBC Radio 4 series about life's big questions - A History of Ideas.

This project is from the BBC in partnership with The Open University, the animations were created by Cognitive.