Neurobiologist and lecturer of Physiology at the University of Cambridge Colin Blakemore explores speech as the vehicle of our language in the fifth Reith lecture from his series entitled 'Mechanics of the Mind'. He investigates how we evolved to speak and questions whether human brains are mentally better equipped to interpret the syntax of language.

In this lecture entitled 'A Burning Fire', Professor Blakemore moves between scientific experiments with chimpanzees using sign language to the legendary tales of children growing up without a language. Through these examples he tries to explain why humans have advanced their communications into the complicated language we have today.