At what point in history did social exchanges within a group turn into economic transactions? Hunter-gatherer groups, living in almost complete self-sufficiency, probably had no need for commerce. Goods produced through collective labor were likely shared in a way that freed people from reciprocal obligations and created no power relations. Goods were not compared with one another and had only use value. They did, however, have social value. Exchange became more complex when traded goods were no longer acquired to satisfy an immediate need, but for subsequent exchanges aimed at acquiring other goods. As soon as a particular commodity becomes established within a group as a general equivalent through which any other commodity can be acquired, it performs the function of money. Aristotle describes the very essence of the monetary system in his Nicomachean Ethics:
> "To equate things and services, there must be a common measure. That measure is money; it makes the most disparate things commensurable. Without this equation, there can be neither exchange nor society."
Gold: an irrational choice =====================================================================================================
At first, the "common measure" was a material good: axes (notably in Gaul), salt, or, more generally, ingots of precious metals. These can be viewed as reference standards, revealing the multidimensional nature of the monetary system and allowing any unit used to measure one good to be converted into any other. One may wonder why gold was chosen almost universally as the standard, even though it no longer serves as a guarantee. The metal is reasonably scarce yet common enough to provide a basic medium for exchange. Its qualities of inalienability are well known. Nevertheless, its role in industry has always been marginal. We can manage without gold more easily than without copper, iron, or aluminum. Its use in goldsmithing goes beyond any genuine need. Perhaps the irrationality of this choice owes more to magic than to objective reality…