I recall from my history of economic thought course (it's been a while) that the ancient Greeks viewed the value of both sides of an exchange as being equivalent. That's a pretty normal view historically, but it obviously misses the subjectivist insights from the Marginalist Revolution: that each side of an exchange perceives what they received as more valuable than what they gave in return.
That led to a skepticism of merchants who accumulated gold, because the implication was that they could only be profiting by ripping people off systematically.
Complicating an exchange by including several other goods makes it much less obvious that someone is profiting.
It's interesting, too, that until Aristotle there never has been any profound theory or attempt to develop an economic theoretical thinking that went beyond the ''oikos'' as a simple form of social and fiscal household.
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You always have to wonder if there was previous work, or even if Aristotle had more elaborated thoughts, since so much was lost with the Library of Alexandria.
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That's right. But my observation always has been that the antique tried to leave economics where it belongs: in the hands of the merchants...
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