Hmm. That makes more sense in that it allows the relationship to be precisely calculated, but that doesn't seem to me to be the argument he actually makes. It's strongly implied throughout (especially in the passage about the two sons) that the 'value' here is one being assigned by an independent observer, not by either the king or the prisoner -- namely society.
Also, I don't think it makes sense to say that you can be forced to value anything. The prisoner would trade more life for pleasure if he could, therefore he values pleasure more highly than the current 'exchange rate'. He isn't allowed to make the trade, but that doesn't mean his values have been changed. (For an analogy, imagine that you want to sell your trumpet for $100 at the local pawn shop, but the pawn shop is currently closed. Does this mean that you value your trumpet at more than $100 until the pawn shop opens again?)
It's strongly implied throughout (especially in the passage about the two sons) that the 'value' here is one being assigned by an independent observer, not by either the king or the prisoner -- namely society.
Yes, and this is also backed up by the resolution to the first story: the exchange rate for the guilders was the most valuable things they could be traded for on the market.
Available in PDF here, the short story in question may appeal to LW readers for its approach of viewing more things than are customary in handy economic terms, and is a fine piece of fiction to boot. The moneychanger protagonist gets out of several sticky situations by making desperate efforts, deploying the concepts of markets, revealed preferences, and wealth generation as he goes.