The following is an excerpt from Don Boudreaux on his blog, Cafe Hayek. Be sure to click through and read the whole post.

Deirdre [McCloskey] acknowledges that a great deal of exploitation has occurred throughout history – exploitation that enriched some people and impoverished others. (Indeed, such exploitation continues to occur in various forms and degrees.) But the enormous, sustained, and widespread growth in the material wealth of market-oriented societies over the past 200 years is far too great to be the product of extractions from poor people. An armed robber can indeed gain more material wealth for himself if he successfully confiscates the pennies, Metro cards, and cell phones from the purses of some hapless, poor victims of his predations. But he isn’t going to get rich preying upon such people – and such people will not get rich by being preyed upon. If we group these two classes of people – armed robbers, and poor victims of armed robbers – into a unit called “society,” no one imagines that that society grows richer through the exploitation by members of one of these groups of members of the other.”]