According to the commodity-money theory, championed by the Austrian school of economics and initiated by Carl Menger, money emerges naturally from a barter economy faced with the problem of the double coincidence of wants. In this vision, individuals spontaneously converge on intermediate goods that facilitate exchange—goods not intended for direct consumption but commodities recognized for their capacity to be widely demanded.

These monetary goods must possess qualities identified since Aristotle: they must serve as a store of value, a means of exchange, and a unit of account. Economic agents gradually identify, accumulate and save them, thus initiating their emergence as money. This process is entirely spontaneous—money represents a natural market response to the problem of coordinating exchanges, without the conscious intervention of an authority.

Anthropologists such as David Graeber dispute this view, invoking the "barter myth". Their argument: no complex civilization based solely on direct barter has ever been documented. Rather, the primitive societies studied used systems of informal credit and reciprocity. Graeber asserts that debt preceded barter, citing thousands of Mesopotamian tablets documenting credit relationships.

However, this criticism is based on a restrictive definition of barter. As Menger pointed out back in 1892, barter goes beyond the simple direct exchange of goods for goods. It also encompasses deferred transfers, services for wages, and exchanges with temporality—what Menger called "unilateral transfers between individuals". This extended form of barter can coexist with credit systems in restricted circles of trust.

The absence of evidence is not evidence of absence. Austrian economists acknowledge that no complex society can sustain itself solely on direct barter, necessitating the emergence of money.

The debate is crystallizing around the origin of the Mesopotamian silver shekel. There are two opposing interpretations. The institutional view holds that the temples—true economic and spiritual centers—imposed silver as a currency to structure the economy. The cuneiform tablets, concentrated among the clergy and merchant elites, bear witness to this centralized control.

The Austrian interpretation suggests the opposite: it was the merchants who adopted money for long-distance trade. Faced with the challenge of trading with strangers beyond Mesopotamia's borders—from Anatolia to the Persian Gulf—they needed something universally recognizable, durable, and transportable. Silver was a natural choice because of its intrinsic qualities. The temples simply confirmed a practice already established by commercial usage.

This thesis is based on documented exchanges between Kanesh in Anatolia and Assur, where merchants exchanged textiles for silver metal—not for its material utility, but as a store of value. These transactions went beyond mere barter, revealing the existence of a genuine commodity currency.

Economist Richard Radford, a prisoner in Germany during the Second World War, documented a fascinating case of spontaneous monetary emergence. In the camps, cigarettes naturally became the unit of exchange—divisible, standardized, widely accepted. Even non-smokers adopted them, recognizing their universal exchange value.

This microcosm illustrates the Austrian principle: faced with the problem of coordinating exchanges, individuals spontaneously converge on the most "saleable" good. No authority imposed cigarette money; it emerged from the daily practice of prisoners seeking to optimize their exchanges.

Essentially, money represents the convergence of individual preferences towards an accepted common good. Mesopotamian merchants, like Radford's prisoners, identified the good that minimized the uncertainty of future exchanges. This selection does not await the authorization or imposition of a central authority—it emerges from the practical rationality of economic actors faced with the challenges of exchange.

The debate between spontaneous emergence and conscious institution remains open, as historical evidence is fragmentary. But the Austrian analysis offers a coherent explanation: money was born out of the practical needs of commerce, with authorities merely institutionalizing practices already established by market usage.