My buddy Joel Achenbach at the Washington Post has given us a "cheat sheet" on the history of the entire world. Click to see it. Here are some highlights: Hunters and gatherers discovered that if they stopped hunting and gathering and grew crops instead, more people could live far more difficult lives.... The barbarians kept sacking Rome. Other cities got invaded, conquered, destroyed, but only Rome was allowed to be “sacked.” ... People dug up coal and burned it. ... Joel doesn't ...