I'm still not sure what you meant by Keynesian, but that is a nice link to a very thorough discussion about bitcoin from 2011. Supply, Demand, What is Money, a

I'm still not sure what you meant by Keynesian, but that is a nice link to a very thorough discussion about bitcoin from 2011. Supply, Demand, What is Money, and What is Valuable are all unresolved questions even in 2017. The need for money fundamentally stems from needing a way to trade dissimilar goods (like hens for milk). Nations making money is a whole separate issue that has delayed the progress of mankind for millenia