Thanks. I have read that post by Eliezer before. The issue with monetary economics is the number of variables. Money is one half of every single transaction, in a sophisticated economy.
Re definitions, the meaning of rational there is that the person acts based on his internal map of the world (this is how Mises used the word way back when and it is part of parlance in Misesian economics). It does not mean what LW thinks it means.
Re unknowable desires, it is a way of saying that economically relevant desires are revealed by economic actions. Demand means being willing and able to pay.
Semantic issue in both cases :)
I mean that in a monetary economy, one always buys goods and services with money. One side of the transaction is money, whatever it is. Sophisticated here means an economy that has progressed beyond barter and developed a medium of exchange and a store of value, ie, Money.
Economies that have multiple currencies are unsophisticated...?