history-society

Trust Is Expensive to Build and Cheap to Destroy In 1993, a hedge fund called Long-Term Capital Management attracted the most prestigious team ever assembled in finance. Two Nobel Prize-winning economists. A former vice chairman of the Federal Reserve. The intellectual elite of quantitative trading. Their models were brilliant. Their

The Economics of Trust Every transaction you make—buying coffee, signing a contract, clicking "I agree"—depends on trust you've never thought about. Trust that the coffee isn't poisoned. Trust that contracts are enforceable. Trust that the company will do roughly what it promised.

Synthesis: Engineering What Spreads This series has laid out the mechanics: how beliefs infect through networks, how the distinction between simple and complex contagions determines what can spread, how emotions propagate beneath conscious awareness, how cascades can detach consensus from truth, how network topology creates the physics of transmission, how

R0 for Ideas Epidemiologists have a number that captures everything about a disease's spreading power: R0, the basic reproduction number. It answers a simple question: on average, how many people will one infected person infect? If R0 is less than 1, the epidemic dies out. Each infected person

Network Topology: Small Worlds In 1967, social psychologist Stanley Milgram ran an experiment that would become one of the most famous in history. He gave letters to random people in Nebraska and Kansas, addressed to a stockbroker in Boston. The catch: participants couldn't mail the letters directly. They

Information Cascades In 1992, economists Sushil Bikhchandani, David Hirshleifer, and Ivo Welch published a paper that explained why everyone suddenly believes the same thing—even when the thing is wrong. Their model was called "information cascades," and it solved a puzzle that had haunted economics for decades: how