Ah, well, as I suspected, there is no convenient definition. But of course, if we are serious about this, there is no such thing as a "pure free market"--even theoretically. Because any exchange presupposes a prior agreement on participation in a civil society and, more specifically, what constitutes property (you can't exchange what you don't own). The favorite "Robinson Crusoe" (or is it "Jack and the Bean Stock"?) example of "free" exchange presumes Crusoe (or Friday) doesn't just whack the other guy on the head. I.e., that both Crusoe and Friday bring with them a cultural framework that recognizes the value of collaboration. The absence of civil society puts us in the "state of nature"--and whether Hobbes or Locke, it always reduces to a state of war, not a market! Fred Carstensen