As ever, you have given me lots to think about and respond to all at the same time!

Money is an "intermediate unit of exchange." But it is a unit of exchange that is based upon labor. If you have no labor ... you have no currency.

Exactly, so I'm imagining a world whereby the labour done in the world is done by machines which are energy positive. So all the work that needs to be done, is done for us and therefore taking away a need to represent value via work done.

I get your point about intrinsic value, however gold does have a use beyond being a shiny bauble for us to adorn our bodies and faces with. It is incredibly useful in computing, and in fact there are people in certain African countries that mine gold from discarded computers.

One of the problems with so many future-focused thought experiments is that they're done in isolation, i.e., they consider only science, technology, biology, psychology, economics, etc. ... individually. And, this would seem like good practice as it adheres to the scientific method ... only change one independent variable at a time.

The problem is that economies are highly complex with hundreds of inter-connecting variables, and considering one variable independently, in isolation from the rest, is simply unrealistic.

Agreed, it is a big problem when engaging in futurethink to use one variable as a deterministic principle, along with the fact that we try and second guess tech that simply hasn't been invented yet and the impact of said technology on our lives. It's an interesting way to go about it though, perhaps after some time of changing variables we will have some kind of bigger picture.

Your analogy about the rat experiment is also interesting ............But this is cheating, no?

Yes and no, it is because of course it engineers a completely false situation, however as you point out, the experiment does show that the rat eats for dopamine, and the pain of hunger becomes insignificant next to that desire. However it does give us insight into what really drives us as biological entities, and I believe that may also give us a clue as to how we may behave in a world whereby basic need no longer gave us the dopamine rush we used to get.

I was indeed travelling getting a much needed break, I love the title and I'm off to read it right now! :-)

Cg