1. Out of the trees : Playboy and the Pleistocene ; The forest for the trees: the social side of things ; Organizing our thinking as trees
3. Copying brain, social mind : More really is different ; Why copy? ; The social brain: organized in trees ; The social mind and collective memory
4. Social learning, en masse : Models of social diffusion ; Anyone for "less nuanced"? ; Why "cold fusion" is different ; The idea and the virus ; Heard that name before? ; Traditions
5. Cascades : Unintended cascades ; "Impact" cascades ; Not solid ground ; Things get complex ; When power laws cascaded ; Avalanches and wildfires ; Cascades in highly connected networks ; Trees, again ; Learning from cascades
6. When in doubt, copy : Extending the game ; Long tails ; Copycats ; How are people copying?
7. Mapping collective behavior : A map with four regions ; The age of "what she's having" ; Back in the deli.
