Throw together smart, attractive, ambitious, and energetic young men and women (or men and men, or women and women, for that matter)1 for 16 hours a day of high-pressure, high-stakes work seven days a week, 52 weeks a year. Make sure they develop an elite esprit de corps of shared suffering and accomplishment, compounded by societal envy and disapproval of what they do, and give them rare opportunities to blow off steam together in dark nightclubs and bars and the company of way too much alcohol. It’s a wonder every female investment banker under the age of 30 isn’t pregnant all the time.