economists thus predicted that all (100%) non-monetary economies would be barter economies. Empirical observation has revealed that the actual number of observable cases—out of thousands studied—is 0%. Similarly, the number of documented marketplaces where people regularly appear to swap goods directly without any reference to a money of account is also zero. If any sociological prediction has ever been empirically refuted, this is it... Meanwhile, all textbooks continue to report the same old sequence: first there was barter, then money, then credit.
I believe currency arose to systematize temple tribute. That is, in stage 1 peasants send grain to the temple, and the temple gives the grain to soldiers and road-makers (the earliest writing records these transactions). In stage 2 the temple gives the soldiers grain-tokens and the soldiers given them to the peasants for food, and the peasants pay tribute back to the temple in tokens. Now only tokens need to be stored and transported. Empires which circulated tribute-tokens instead of cartloads of grain could get geographically bigger. Tribute-tokens evolved into currency (here is an academic paper setting out this view in more detail)
A larger point arising is that money, exchange-relationship, and ownership itself, are not primal features of the world, or of humanity. Ownership exists within a context of social values and responsibilities (thus refuting Libertarianism). And money is not a fuel which can be used up, it's a medium which goes round and round (thus refuting right wing economics).
It's amazing to me to hear ordinary people saying at the moment that the public sector uses up money created by the private sector. That is not how money works. Clearly in the temple-tribute model what matters is the ratio of people growing grain, to people eating grain, but sector is irrelevant. Similarly, a modern train driver is equally productive whether he is employed in the public sector, as in France, or the private sector as in England. It is absurd to think that a train driver in France is somehow a drag on the economy, and in England an asset. Or a nurse in England is a burden but not a nurse in America. What matters is: are they making useful stuff.
I think a moment's thought shows us how false these models of economics are. And yet this false story is repeated everywhere, and most sickeningly, it's the basis of the destruction of the British economy. Its throat has been cut and it's bleeding out. All because of a false view of money.