[W]hile you may argue that it makes no logical sense for an evil Paladin to be the martial equal of a good one, I'd posit that you're arguing logic in a game where wizards can cast an identify spell using a pearl worth "at least 100 gold pieces". And nothing anywhere explains how to calculate who determines the worth of that pearl. Are the pearls used to identify magic items in the desert smaller and more flawed than the ones in the fishing village that has pearl cultivation beds? That's a screwed up metaphysical system where market forces determine the efficacy of magic.So what is a pearl worth? The usual answer is that it is worth what someone will give for it. This may lead to results that seem absurd in real life, too. Sometimes people who have a lot of money push the value of apparently trivial objects well above what ordinary people could afford. Is the single copy of Wu Tang Clan's Once Upon a Time in Shaolin really worth millions of dollars?
To dispute that it was, you would have to have some other standard than exchange to measure what a thing is "really worth." Many economic theories simply lack the furniture to argue about whether or not the pearl is "really worth" 100 gold pieces, or the album is "really worth" millions of dollars. Other theories that do are largely discredited: Marxists can talk about "surplus value" being extracted from laborers, but Marxist economics has never managed to work anywhere.
I was thinking about this today because of an article in the NYT that purports to show that as women take over in male-dominated fields wages drop.
If this is true, under the exchange theory of value the work of women is "really worth" less just because people are willing to pay less for it. It is, presumably, the same work. The work was "really worth" more if a man did it in a male-dominated field, and now is "really worth" less because women have entered the field. Is that right?
Well, one thing that would make it plausible is that womens' entry increases the supply of labor for that particular job; now everyone's labor is worth less in that field just because of the law of supply and demand. That may be the real explanation, but I want to set it aside for the purpose of this discussion. I'm interested in a theoretical question.
What interests me is -- as usual -- whether there is a moral question that should override the economic question. It often bothers me that so much seems to be for sale. I like to think that at least some things ought not to be traded in the market. Even in the market, too, I think some relationships are adequately unfair that they should be banned even if both parties to the trade are willing.
Here is a moral principle of fairness (which Aristotle said is an important component of justice, and which Rawls said was the whole of justice). It seems to be out of order with the economic principle, maybe, if the explanation is not merely an increased labor supply.
Does it show that the exchange theory of value is incomplete or inadequate? In Mike's D&D example, I thought the pearl would prove to have an objective value if it could be used for the spell. Does fairness perform something of the same role as magic, but in the real world? Or should we continue to discard other concepts than exchange value, and say that fairness does not apply?



