Money is not as simple as the coins or notes in your pocket.
It has a history; it has constantly evolved, together with related social technologies like credit, banking, accountancy and the state;
It is very different to even fifty years ago ; a world system of fixed exchange rates and restricted capital flows has changed into an unstable interlinked, complex web;
We are not very good at understanding its nature, as shown by inflation - the cancer of money- asset bubbles and financial disasters.
Money depend on institutions and trust and confidence.
If the whole economy is changing, the nature of money inevitably is too.
We use money to keep the score ... But what is it for?