Economic historian Karl Polanyi has argued that where barter is widespread, and cash supplies limited, barter is aided by the use of credit, brokerage, and money as a unit of account (i.e. used to price items). All of these strategies are found in ancient economies including Ptolemaic Egypt. They are also the basis for more recent barter exchange systems.
No, said Mises, for if taken back far enough, there comes a point at which money first emerges as a medium of exchange out of a pure barter economy Prior to this, it is valued only for its non-monetary uses as a commodity The demand for money is therefore pushed back to the last day of barter, where goods are traded only in direct exchange, and where the temporal element of the regression theorem ends It is in this way that all charges of circularity are obviated.
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.