On Mon, 16 Jan 2012, Mike Beggs wrote:
> For Marx, money is a pre-condition of generalised commodity exchange,
> it didn't historically evolve out of it. But once commodity exchange
> is generalised, it tends to reproduce money and change its form and
> function.
That's perfectly correct. But whatever Marx says in this passage (and I think it's disputable) the beginning of Capital Vol I is the most detailed example of the ideal barter story I can call to mind. First you have exchange of good for good, i.e., pure barter; then you have a generalized equivalent, i.e., a trade good in terms of which other things are measured; and then that general equivalent (or a representation thereof) becomes money.
There is nothing in there about real origins of money as a unit of account for states to compute taxes; the several stages that come thereafter; and then some account of how generalized exchange battens on to it and changes its dynamic. Rather the dynamics of exchange are projected backwards.
Michael