I just went to a free lecture at Melbourne Uni, on the invention of money by the Greeks in the sixth century.  It was pretty interesting:  the lecturer was fairly engaging to listen to, which is always a bonus.  I wasn’t entirely convinced by what he said about the invention of money itself – it seemed a bit vague, although admittedly the guy did say that the details were all in his book (plug, plug – he did it in quite a self-effacing way, though).  The more interesting side of it was the connection between the development of philosophy and money at the same time, in the same place (and he would have talked about drama, in particular tragedy, too, if he hadn’t had all of his time taken up by philosophy).  He defined philosophy as the view that the universe is an understandable system governed by uniform, impersonal forces.  The early philosophers all seemed to think that the entire universe is made up of one substance, in different forms.  The lecturer said that this was a result of Miletus (where the philospohers lived) being a monetised society.  Money was the most powerful thing in a non-monarchical society; it was capable of being exchanged for anything, and everything could be exchanged for money; and it was impersonal.  Viola.  Philosophy as we understand it.  Pretty interesting idea.