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The man who arguably founded modern economic theory, the 18th-century Scottish philosopher Adam Smith, popularized the idea that barter was a precursor to money. In The Wealth of Nations, he describes an imaginary scenario in which a baker living before the invention of money wanted a butcher’s meat but had nothing the butcher wanted.“No exchange can, in this case, be made between them,” Smith wrote.
Bartering may sound like a style of commerce more fitting to a backwater marketplace than a modern capitalist environment. According to the International Reciprocal Trade Association—an organization created to promote “just and equitable standards” in modern bartering—the U.S. barter market is a staggering $12 billion annually. In other words, $12 billion worth of goods and services are traded every year without any currency changing hands. Scott Whitmer, founder of trade exchange company Florida Barter, says that while 2011 saw positive signs of an economic recovery, many small and medium-size companies are still struggling. “Bartering has continued to help many [of these] companies grow and conserve cash,” he says. Though Florida Barter enjoyed a record 2011—a 12 percent increase in total trade volume; more than $17 million worth of trades among the 1,600 clients—Whitmer says bartering as a business practice is still in its infancy, “on the cusp of exploding.”
When barter has appeared, it wasn’t as part of a purely barter economy, and money didn’t emerge from it—rather, it emerged from money. After Rome fell, for instance, Europeans used barter as a substitute for the Roman currency people had gotten used to. “In most of the cases we know about, [barter] takes place between people who are familiar with the use of money, but for one reason or another, don’t have a lot of it around,” explains David Graeber, an anthropology professor at the London School of Economics.

But the harm may go deeper than a mistaken view of human psychology. According to Graeber, once one assigns specific values to objects, as one does in a money-based economy, it becomes all too easy to assign value to people, perhaps not creating but at least enabling institutions such as slavery (in which people can be bought) and imperialism (which is made possible by a system that can feed and pay soldiers fighting far from their homes).