Sapiens: A Brief History of Humankind

by Yuval Noah Harari

In fact, even today coins and banknotes are a rare form of money. The sum total of money in the world is about $60 trillion, yet the sum total of coins and banknotes is less than $6 trillion.7 More than 90 per cent of all money – more than $50 trillion appearing in our accounts – exists only on computer servers. Accordingly, most business transactions are executed by moving electronic data from one computer file to another, without any exchange of physical cash. Only a criminal buys a house, for example, by handing over a suitcase full of banknotes. As long as people are willing to trade goods and services in exchange for electronic data, it’s even better than shiny coins and crisp banknotes – lighter, less bulky, and easier to keep track of. For complex commercial systems to function, some kind of money is indispensable. A shoemaker in a money economy needs to know only the prices charged for various kinds of shoes – there is no need to memorise the exchange rates between shoes and apples or goats. Money also frees apple experts from the need to search out apple-craving shoemakers, because everyone always wants money. This is perhaps its most basic quality. Everyone always wants money because everyone else also always wants money, which means you can exchange money for whatever you want or need.