The Evolution and Function of Money

Key Insight

Early human societies, from hunter-gatherer bands to agricultural villages, operated primarily on economies of favors and obligations, with limited barter for rare external goods. However, the rise of cities, kingdoms, and improved transport infrastructure fostered specialization, creating full-time professions like shoemakers and vintners. This specialization made simple barter impractical for large-scale cooperation among strangers due to two critical limitations: the immense complexity of calculating exchange rates and the 'double coincidence of wants' problem, where each party must desire what the other offers. For example, an apple farmer needing shoes would have to navigate thousands of exchange rates, and the shoemaker might not want apples.

To overcome these inherent limitations, societies developed money, a purely mental revolution involving the creation of a new inter-subjective reality based solely on people's shared imagination. Money is defined as anything systematically used to represent the value of other things for the purpose of exchanging goods and services. It allows people to quickly compare values, easily exchange items, and conveniently store wealth. Diverse forms of money have existed, from Sumerian barley money (around 3000 BC, measured in silas, where a male laborer earned 60 silas a month) and cowry shells (used for approximately 4,000 years across various continents, still accepted in British Uganda in the early twentieth century) to cigarettes in prisons and, overwhelmingly today, electronic data.

Currently, physical coins and banknotes constitute less than $6 trillion of the world's total $60 trillion money supply, with over 90 percent existing as electronic data on computer servers. Money's most basic quality is its universal desirability: everyone accepts it because they trust others will also accept it, thereby facilitating the acquisition of any desired good or service. This makes money a universal medium of exchange, capable of converting almost anything into anything else – for instance, a discharged soldier's brawn into knowledge through military benefits funding college tuition. Moreover, money allows for the easy and cheap storage and transportation of wealth, unlike perishable goods or immobile assets like real estate, making complex commercial networks and dynamic markets feasible and significantly contributing to their expansion.