money has no essence. It's not "really" anything; therefore, its nature has always been and presumably always will be a matter of political conten­tion.

But if Smith was right, and gold and silver became money through the natural workings of the market completely independently of governments, then wouldn't the obvious thing be to just grab control of the gold and silver mines?

In fact this is precisely the logic on which the Bank of England—the first successful modern central bank—was originally founded. In 1694, a consortium of English bankers made a loan of £1,200,000 to the king. In return they received a royal monopoly on the issuance of banknotes. What this meant in practice was they had the right to advance IOUs for a portion of the money the king now owed them to any inhabitant of the kingdom willing to borrow from them, or willing to deposit their own money in the bank—in effect, to circulate or "monetize" the newly created royal debt. This was a great deal for the bankers (they got to charge the king 8 percent annual interest for the original loan and simultaneously charge interest on the same money to the clients who borrowed it) , but it only worked as long as the original loan remained outstanding. To this day, this loan has never been paid back. It cannot be. If it ever were, the entire monetary system of Great Britain would cease to exist.

Money has always been a particular problem for revolutionaries and anti-capitalists. What will money look like 'after the revolution'? How will it function? Will it exist at all? It's hard to answer the question if you don't know what money actually is. Proposing to eliminate it entirely seems utopian and naive.

It affects every aspect of our lives, is often said to be the root of all evil, and the analysis of the world that it makes possible - what we call 'the economy' - is so important to us that economists have become the high priests of our society. Yet, oddly, there is absolutely no consensus among economists about what money really is.

Consensus isn't just about agreement. It's about changing things around: You get a proposal, you work something out, people foresee problems, you do creative synthesis. At the end of it, you come up with something that everyone thinks is okay. Most people like it, and nobody hates it.