Bartering is based on a simple concept: Two individuals negotiate to determine the relative value of their goods and services and offer them to one another in an even exchange. It is the oldest form of commerce, dating back to at time before hard currency even existed. (Learn more about how bartering evolved, read The History of Money: From Barter To Banknotes.)
For one thing, the barter myth “makes it possible to imagine a world that is nothing more than a series of cold-blooded calculations,” writes Graeber in Debt. This view is quite common now, even when behavioral economists have made a convincing case that humans are much more complicated—and less rational—than classical economic models would suggest.

Her answer came, finally, in an unlikely place: at a bar on Robson Street in Vancouver during the Winter Olympics. It was close to midnight, and she was waiting in line for a drink. All around her, people were partying—except for the two women in front of her, who were dissecting the differences between tax-free savings accounts and RRSPs. Simmons barged in to their conversation. “What do you want to know about TFSAs?” she asked. “What’s your goal?” She pulled the two aside and, for 20 minutes, gave an impromptu finance session. As a gesture of thanks, the two women bought Simmons and her group a round of beer. “I can’t afford financial advice,” one of them told Simmons, “but at least I can give everybody here a beer.” Then, Simmons felt like a cartoon megawatt bulb appeared over her head. It is all you can do, she thought. It is all you can do. There, in the middle of the crowded bar, she blurted, “Oh my god! I’m bringing barter back!”

Anthropologists have argued, in contrast, "that when something resembling barter does occur in stateless societies it is almost always between strangers, people who would otherwise be enemies."[6] Barter occurred between strangers, not fellow villagers, and hence cannot be used to naturalisticly explain the origin of money without the state. Since most people engaged in trade knew each other, exchange was fostered through the extension of credit.[4][7] Marcel Mauss, author of 'The Gift', argued that the first economic contracts were to not act in one's economic self-interest, and that before money, exchange was fostered through the processes of reciprocity and redistribution, not barter.[8] Everyday exchange relations in such societies are characterized by generalized reciprocity, or a non-calculative familial "communism" where each takes according to their needs, and gives as they have.[9]