Dan Ariely is one of the most famous behavioral economists in the world. And in his latest act, he's attempted to apply his research to investing. His five-year-old firm Irrational Capital searches out companies that foster human capital: that companies which do a better job of nurturing their employees see stock market outperformance. In this episode, we talk about why human capital matters, how to measure it, and what kind of investment returns he's seen by betting on it.