How can our brain be capable of speech? Does the faculty of speech find its roots only in a very precise part of the brain, an opinion which Paul Broca, who was the first to identify apahsia, upheld? How does the subtle arrangement of cells under our skull give birth to what is the basis of our culture?Through the study of the neurology of aphasia and some other disorders due to lesions in the brain, Olivier Sabouraud, who is a neurologist and a professor, proposes here an extraordinary survey of the foundations of speech, enriched by recent discoveries in clinical research.