A dispatch in Friday’s New York Times noted in passing that the chief executive of Lehman Brothers, Richard Fuld, has seen “much of his wealth disappear.” The value of his stock and options in the company had fallen by late last week to about $40 million from the $956 million they were worth at their peak in early 2007. We would say that the evaporation of $916 million in personal wealth over the course of a year and a half was unprecedented, except that the chief executive of Bear Stearns, James Cayne, lost $1.1 billion in stock and options over an even shorter period in the collapse of that investment bank. When he sold his stake earlier this year it was reportedly worth about $60 million.

This is a lesson to remember the next time the left denounces the gap between rich and poor in America, or between the merely rich and the so-called mega-rich. Many of the super-rich get that way by taking on risks that others shy away from. And the mega-rich don’t always stay that way. The dynamism of a capitalist system that creates great fortunes can also destroy them. To put it another way, it doesn’t always require the imposition of a death tax to prevent a billion-dollar fortune from being passed along to the next generation.

Messrs. Fuld and Cayne aren’t any less smart or talented or hardworking than they were two years ago. Nor are any of the other Bear Stearns or Lehman employees whose net worth has declined dramatically. Nor is it a given that those who have lost great fortunes will be forever unable to restore them. There are figures in history who have lost and made and lost and made several fortunes. The thing to treasure is a system that enables people to dare, to take great risks, to reap great rewards, and to maximize what economists like to call their own human capital.