Positive feedback--when A produces B, which in turn produces even more A--drives not only abrupt climate changes, but also disruptive events in economics and finance, from asset bubbles to debt crises, bank runs, even corporate corruption. But economists, with few exceptions, have ignored this reality for fifty years, holding on to the unreasonable belief in the wisdom of the market. It's past time to be asking how markets really work. Can we replace economic magical thinking with a better means of predicting what the financial future holds, in order to prepare for--or even avoid--the next extreme economic event? Here, physicist and acclaimed science writer Mark Buchanan answers these questions and more in a master lesson on a smarter economics, which accepts that markets act much like weather. Market instability is as natural--and dangerous--as a prairie twister. With Buchanan's help, perhaps we can better govern the markets and weather their storms.