Economics should be under no illusion that central banking will ever become a science. - Jürg Niehans

There is a widespread impression today that the history of economics is a sequence of revolutions and counter-revolutions, successive schools rising to dominance just to be deposed in a crisis by another school. According to this view, paraphrasing Marx, all history of economics is a history of school struggles, punctuated by revolutions.

Money is here called the a medium and not, as customary, a unit of account because, clearly, money itself is not a unit, but the good whose unit is used as the unit of account.

If one could be perfectly certain that everybody always stays within his budget constraint, everybody could be allowed to obtain goods without a specific quid pro quo.