My position on relativism

Brad Delong has a fun not-Socratic dialog post.  Mainly he shows the implications of seeking Pareto optimality.   That sort of optimality is about seeking any change that leaves no one worse off and at least some people better off.  The criteria to leave no one worse off means that it automatically rejects any proposals with redistributional impacts.  I'm prone to agree with the critique, but I don't quite understand it well enough to properly summarize it.  [Update: Nic's explained it to me with formulas.  Quick summary: The marginal utility of money depends on how much money you have already.  $1 is worth more to a beggar than a millionaire.  So if all that matters is the total amount of money in the system then the millionaire has far more social value than the beggar.  If everyone has similar value, than more money to the beggar should matter more than more money to the millionaire.]

I particularly enjoyed the final bit:

Thrasymachus: "Ah. Marx thought unveiling was a good thing. I think it is neither good nor bad, for 'good' like 'justice' is really just another word for the interest of the stronger party."

Glaukon: "And we gave you tenure here at Berkeley?"

Thrasymachus: "Shhh! The humanities departments still think relativism is sexy. They haven't yet figured out that to assume a position of relativism--like the claim to be neutral on issues of distribution--is really a statement that you are on the side of the powerful."

Agathon: "And are you?"

Thrasymachus: "It is the just and the good--or, rather, the 'just' and the 'good'--thing to do.

Unpacking things a bit, if relativism just means taking the side of the powerful, why is it popular in some sections of the humanities?  The answer, I suspect, is that it is scene as an alternative to an absolutist scale established by the most powerful party.  Relativism can work like federalism, each local set of powers that be can have a different set of values.  The appeal of the more local setup is that the values will tend to reflect local conditions better than the set of values laid down by the hegemon.

However, I think it's ultimately just a cop out.  There's other ways to include local cultural conditions and sources of absolute values that aren't divine or simply based on the dictates of some other powerful actor.