Systems-Thinking

In the early 1990s, British anthropologist Robin Dunbar made a curious observation while studying primates. He found a correlation between the size of a primate’s neocortex (the brain region handling social relationships) and the size of its social group. Chimps, with smaller neocortices, lived in groups of ~50. Gorillas: ~30. Humans, with the largest neocortices, should be able to maintain stable social relationships with about… 150 people. That’s it. Not 500. Not 1,000. 150. ...

In medieval England, villages had common grazing land—the “commons”—where all villagers could graze their sheep. Each shepherd faced a decision: How many sheep should I graze? The logic was simple: Adding one more sheep: I get 100% of the profit Cost of overgrazing: Shared among all shepherds So every rational shepherd added more sheep. And more. And more. Until the commons was destroyed. Overgrazed. Barren. Worthless to everyone. This wasn’t malice. Each shepherd was acting rationally in their own self-interest. ...