Money
The Story Of Humanity
By David McWilliams
Category: History | Reading Duration: 19 min | Rating: 4.6/5 (45 ratings)
About the Book
Money (2023) explores the evolving relationship between humans and money over the past 5,000 years, from its origins in Mesopotamian clay tablets to modern cryptocurrencies. It traces how money has continually adapted to changing technologies, economies, and societies, shaping human behavior as much as being shaped by it.
Who Should Read This?
- History enthusiasts curious about money’s evolution
- Economics students seeking engaging, real-world insights
- General readers interested in financial systems and society
What’s in it for me? Learn how money transformed humanity
You tap your card for coffee. Your phone pings with a salary notification. A few swipes and your rent is paid. It all feels seamless: instant, effortless, invisible.
But have you ever stopped to wonder what money actually is? Not just the paper or plastic in your wallet, but the concept behind it? Why does it hold value, and how did we agree on that value in the first place? In this Blink, we’ll follow David McWilliams as he peels back the layers of this everyday mystery. This isn’t a dry lecture on coins and banks. It’s a bold, sweeping journey through 5,000 years of human civilization – viewed through the lens of its most powerful invention.
From ancient Mesopotamian clay tablets to Bitcoin and beyond, money has shaped how humans live, work, fight, trade, and dream. So before you make your next transaction, stop to think. The story of money is also the story of us. And once you see it, you can’t unsee it. Let’s explore how money made us – and how, perhaps, we’ve always been making money.
Chapter 1: Money is a social technology
Humans evolved to live in small groups, and our brains were built for this scale of interaction. But when agriculture took root, everything changed. Farming created stable food sources, which in turn led to larger communities. These larger groups brought new challenges: how to cooperate, manage resources, resolve disputes, and trade with strangers.
Our brains alone couldn’t handle the complexity. To keep up, we developed social technologies – non-physical tools like language, law, religion, and eventually, money. Money emerged not as a luxury or convenience, but as a survival tool. It was invented to help humans manage life in large, settled communities. Unlike barter systems, which break down in big populations, money allowed people to measure, store, and exchange value across time and distance. It wasn’t just a means of exchange – it was a way to structure society.
Grain played a central role in this transformation. It could be grown, harvested, and crucially, stored. This storage created a surplus – an energy reserve that could be distributed later. That surplus became the foundation for value. A fixed quantity of grain could represent a day’s labor, the rent of land, or the price of goods. This made it possible to create a standard unit of account.
In Sumer, an early civilization in today’s Iraq, a unit called the shekel was tied directly to a specific amount of barley. Grain, in other words, was the first currency. As a result, the granary wasn’t just a storage site; it was a financial institution. It controlled the grain supply and, by extension, the money supply. When harvests were good, more grain meant more money in circulation. Poor harvests meant scarcity and less liquidity.
This early monetary policy mirrors the modern role of central banks, which regulate currency to stabilize economies. As grain-based money became more sophisticated, it enabled the rise of organized states. Surpluses could be taxed, supporting rulers, bureaucracies, and standing armies. These taxes didn’t just build temples or palaces – they built societies. The more productive the agriculture, the more specialized and complex the society became. Farmers supported priests, soldiers, merchants, and scribes.
The economy could expand beyond mere survival. This shift was monumental. Humans moved from relying on nature’s gifts to creating human-centered systems to manage life. Money, as a social technology, was key to this transition. It allowed civilization to scale, to coordinate, and to build. From granaries to global banks, the journey of money reflects our journey from scattered tribes to complex societies.
Chapter 2: Interest rates changed humanity’s perception of time
Over 5,000 years ago, in the bustling cities of ancient Mesopotamia, a quiet revolution took place – one that fundamentally changed how people thought about time, risk, and value. That revolution was the invention of interest. By putting a price on borrowed money, early societies created a system that connected the present to the future in a completely new way. Imagine a man called Kushim, a beer maker in Sumer, borrowing barley to brew his product.
His loan came with a deadline and an annual interest rate. Suddenly, time wasn’t just about sunrises, harvests, or seasons. It had a price. That interest rate reflected more than just numbers. It told a story about trust, uncertainty, and opportunity. It captured the risks of the future and the rewards of waiting.
This development was groundbreaking. Until then, value was mostly tied to physical goods like grain, cattle, or land. Now, money itself had value simply because it could be lent. The interest rate turned money into a commodity. Lending became an investment in tomorrow. Borrowing became a bet on future success.
For the first time, people could access future income and use it today. That shift was essential in getting capital flowing. It prevented money from sitting idle in the hands of the wealthy and put it to work in the hands of those who needed it. But the implications ran deeper. Charging interest forced people to think long-term. Lending involved judging risk over time – how likely it was that someone would repay a debt years down the line.
The further out the repayment, the greater the uncertainty, and the higher the interest had to be. In this way, interest encoded complex data about the borrower, the local economy, and the level of competition in the market. It became a tool not just for finance but for forecasting. The Sumerians even used compound interest – where interest is added to the principal, and future interest is calculated on that new total. This meant debts could grow dramatically over time, raising the stakes for both lenders and borrowers. It also deepened the sense of urgency around repaying loans.
Borrowers like Kushim didn’t owe a fixed amount – they owed an expanding one. In some cases, default could cost a person their freedom or the freedom of their family. By pricing time, interest created a bridge between today and tomorrow. It made planning, investing, and innovation possible. Long before modern banks or Wall Street, ancient people understood the core principle of finance: money today is not the same as money tomorrow. And it all began with barley, debt, and a new way of seeing time.
Chapter 3: Paper money was only possible in high-trust societies
The introduction of paper money marked a turning point in human history. It wasn’t just a new form of currency – it signaled the rise of a high-trust society. For centuries, money had been rooted in physical value: gold, silver, copper, and coins with tangible worth. Later, it evolved into financial instruments like letters of credit, which were still traceable to individuals or assets.
Paper money was different: it represented value purely because people believed in it. And that belief required a leap of trust. This leap became possible thanks to wider societal changes, particularly the explosion of printed materials following the invention of the printing press. As paper spread beyond monasteries and royal courts, it became a tool for ordinary people. Books, pamphlets, and posters flooded Europe, raising literacy and encouraging independent thinking. If people could question the church and monarchy, they could also question the nature of money.
Why not value a piece of paper if it was guaranteed by a trustworthy institution? This was already happening centuries earlier in China. During the Song dynasty, the government printed paper money on durable mulberry bark using advanced copper-plate technology. These notes, originally based on receipts from pawn shops, became state currency. People accepted them because they trusted the institutions behind them. It was the same principle that would later take root in Europe.
By 1609, Amsterdam had laid the groundwork for a new monetary age with the creation of a new city-operated bank called the Wisselbank. As a small, open trading economy, the Netherlands faced a challenge: foreign money poured in from global trade, and the chaos of multiple currencies threatened stability. The Wisselbank stepped in to centralize and regulate this flow. It converted a mix of foreign coins and bullion into a uniform Dutch currency, the guilder, backed by gold reserves. This ensured consistency and trust, allowing the Dutch to scale their economy. The rise of central banking wasn’t just economic – it was political.
The Dutch state needed funds to protect its trade routes, so it borrowed from merchants to build a navy. In return, the navy secured shipments of goods and wealth from across the world. This cycle of commerce, protection, and reinvestment created a powerful feedback loop. Paper money, issued and backed by a trusted bank, was the lubricant that kept it all running. Paper money worked because people trusted each other, even without personal connections. That trust, institutionalized through banking, allowed trade, investment, and innovation to flourish.
Chapter 4: Today’s money is mostly conjured out of thin air
Modern money is mostly credit. It’s not coins in your pocket or notes in your wallet. In fact, physical cash makes up only about 10 percent of the money in circulation. The rest is invisible – digits on screens, numbers in databases – created by commercial banks through lending.
When a bank approves a loan for a house or a car, it doesn’t hand over existing money. It creates new money, out of nothing, by typing figures into an account. That credit becomes spendable cash, though it never existed before that moment. This system may sound strange, but it has deep historical roots. Money has always had a dual nature. One part is tangible: grain, gold, coins.
The other part is contractual: agreements, IOUs, and promises to pay. In ancient economies, actual currency only came into play when clearing debts. Most transactions were managed through trust, reputation, and written obligations. Physical money was mainly used to settle scores at the end of a deal. As societies became more complex, finance took over. Contracts became more sophisticated, and money became more abstract.
Double-entry bookkeeping, pioneered by merchant bankers in Renaissance Florence, allowed lending to grow without any direct tie to gold or silver. By the time of the Dutch Republic, it was finance – rather than metal-based money – that powered trade. The system evolved not by creating more currency, but by expanding credit. Today, commercial banks are the main creators of money. When a loan is issued, the bank doesn’t move money from one pile to another. It creates it.
That loan becomes an asset for the bank and a liability for the borrower. The entire modern economy is built on these shifting layers of credit and debt. This makes finance incredibly powerful – and risky. Credit can spark innovation and investment. But it can also fuel bubbles and crashes. Because this system operates on confidence and contracts rather than hard assets, small shocks can trigger big effects.
The central bank doesn’t directly control the creation of credit, but it tries to guide it with rules and reserve requirements, like guardrails on a winding road. Understanding money today means understanding credit. Finance is not a side note to currency – it’s the main story. And the story is ongoing. With every loan approved and every tab settled, money is created, destroyed, and recreated. The real economy – jobs, homes, businesses – is shaped not by the coins in circulation, but by the contracts that underpin them.
Chapter 5: Money must evolve to be useful, inclusive, and trusted
Money only reaches its full potential when it is usable and trusted by as many people as possible. Throughout history, money has changed shape to meet the needs of the time – becoming more accessible, practical, and relevant. From shells and silver to credit and digital tokens, each version of money has been shaped by a simple test: does it work for ordinary people? Modern innovation offers a powerful example of this process at work.
While much of the global conversation focused on cryptocurrencies and their flashy marketing, a quiet revolution in money took root in Africa. M-Pesa, launched in Kenya in 2007, transformed basic mobile phone credit into real, usable money. Unlike cryptocurrencies, M-Pesa solved a clear and pressing problem: the lack of access to banking and credit, especially in rural areas. It didn’t need tech billionaires or Wall Street endorsements. It spread because it worked. With M-Pesa, anyone with a mobile phone could deposit money, make payments, send funds, and even access loans.
Using simple text messaging technology, everyday transactions became easier and safer. Before M-Pesa, sending money to rural family members often meant physically handing it to a bus driver and hoping it arrived. That system was costly, slow, and insecure. With mobile money, the risk vanished. A text could do what once took hours of travel and significant fees. Today, over 70 percent of Kenya’s population uses M-Pesa, and the platform is responsible for around 30 percent of the country’s GDP.
Its success didn’t come from hype but from usefulness. M-Pesa fits the environment it grew in. It answered a real demand and empowered people who had been financially excluded. It turned a mobile phone into a bank and phone credit into money. Money evolves just like language. It adapts to fit the needs of those who use it.
Innovations that solve problems thrive, while those that don’t fall away. M-Pesa succeeded because it passed the test that crypto often fails: it was functional, trusted, and inclusive. It proved that money isn’t about status or spectacle. It’s about problem-solving.
In the bigger picture, M-Pesa reminds us that money is a social technology, not just a financial one. It shapes how people interact, invest, and live. When designed for real people, in real situations, money becomes a tool that unlocks opportunity. It becomes not just a means of exchange, but a driver of human progress.
Final summary
The main takeaway of this Blink to Money by David McWilliams is that money is a social technology that evolves to solve human problems. It enables cooperation in large groups, connects present action to future outcomes, and depends on trust to function. Interest rates changed how people value time. Paper money required belief in institutions.
Modern credit is mostly created by banks, not states. And finally, for money to thrive, it must be usable, inclusive, and widely trusted, adapting to meet real needs in real contexts. Okay, that’s it for this Blink. We hope you enjoyed it. If you can, please take the time to leave us a rating – we always appreciate your feedback. See you in the next Blink.
About the Author
David McWilliams is an economist, author, and journalist known for making complex economic ideas accessible to a broad audience. He writes a weekly column for the Irish Times and hosts The David McWilliams Podcast, where he breaks down economics in an engaging, conversational style. He is an Adjunct Professor at Trinity College Dublin and has worked as an economist with institutions including the Irish Central Bank and Banque Nationale de Paris.