Preface; Part I. Puzzles: 1. A natural curiosity: how did language begin?; 2. A peculiar habit: what is language for?; 3. The bother at Babel: why do languages differ so much?; 4. Distinct duties: is language an independent skill?; Part II. Origin: 5. The family tree: the evolutionary background; 6. A devious mind: the basic requirements; 7. Broken air: inherited ingredients; 8. Small beginnings: first steps; Part III. Evolution: 9. The secong word: the emergence of rules; 10. The tower of speech: expansion; 11. Time travelling: extra attachments; 12. Rebuilding on the high seas: keeping going; Part IV. Diffusion: 13. The widening circle: moving outwards; 14. The hidden core: the hunt for universals; 15. The real magician: ruling the rules; 16. Unweaving the rainbow: separating the strands; 17. The endless stair: past and future; Symbols used in the text; Notes and suggestions for further reading; References; Index.