Part I. Preliminaries: The ever-whirling wheel
Collecting up clues
Charting the changes
Part II. Transition: Spreading the word
Conflicting loyalties
Catching on and taking off
Caught in the web
The wheels of language
Spinning away
Part III. Causation:
The reason why
Doing what comes naturally
Repairing the patterns
Pushing and pulling
Part IV. Beginnings and Endings
Language birth
Language death
Progress or decay?