Economist known for his research on immigration, population, and natural resources. He created the political theory of free-market environmentalism and published the groundbreaking 1981 work The Ultimate Resource.
After earning a bachelor's degree in psychology from Harvard University, he received both an MBA and a PhD from the University of Chicago.
He taught for many years at the University of Illinois at Urbana-Champaign.
He married public affairs professor Rita James Simon.
In 1980, he made a famous, public wager with scientist Paul R. Ehrlich regarding the price of metal over a decade-long period. Predicting that several metals would decrease in value, Simon won the wager.