Profit -- getting more out of something than you put into it -- is the original genius of homo sapiens, who learned how to unleash the energy stored in wood, exploit the land, and refashion ecosystems. As civilization developed, we found more and more ways of extracting surplus value from the earth, often deploying brutally effective methods to discipline people to do the work needed. Historian Mark Stoll explains how capitalism supercharged this process and traces its many environmental consequences. The financial innovations of medieval Italy created trade networks that, with the European discovery of the Americas, made possible vast profits and sweeping cultural changes, to