This series is adapted, with permission, from a Chinese-language series by our friend Marcus Ji, who looks at historical events through an economic lens. We have condensed and adapted the original for an international audience.
You make financial decisions all the time, and almost no one was ever taught how. You repay a mortgage, swipe a card, pay a premium, leave your salary in a bank, weigh whether to buy a fund. Each is a financial decision, made mostly by trial and error, with real money as the tuition.
This piece traces how finance grew from nothing into the system you use every day, all because of the development of 10 different innovations throughout the years. And most surprisingly, it shows that the walls that forced the first loan into existence five thousand years ago are all still standing. A Sumerian farmer who had a grain shortage during planting season has to make the same decisions as when you weigh whether to take a mortgage; the way a Song-dynasty note quietly loses its value is similar to how inflation is thinning in your account now.
How to tell if an innovation is necessary
Before we dive into the 10 innovations that led to finance, it’s important to understand what we classify as innovations. There are 2 important criteria:
- The innovation is forced by an unavoidable hard constraint:
Whenever people cooperate across time and distance, they will eventually encounter one or more of these four walls: Time (You have resources now and need them later, or the reverse), Distance (the money is here, but has to be spent there), Risk (a single disaster can wipe out everything you own), and Trust (how to convince strangers that you’d pay them back). - The same solution turns up independently in places that never copied each other:
Sharks and dolphins are only distantly related, yet both evolved streamlined bodies and dorsal fins, because it’s the best design to counter the same constraint – water resistance. Biologists call this phenomenon convergent evolution. Finance is the same. When the same tool appears on its own in Rome, in China and in medieval Italy with no one copying anyone, the cause is likely because they faced the same constraint.
As long as an innovation meets these criteria, they were able to help its civilisation take a step towards the next stage of development. Let’s take a look at the first innovation.
Time: deposits, loans and interest
Around 3500 BCE, Mesopotamia. Humans had barely begun forming cities when they hit its first wall – the wall of time. Farmers usually have a shortage of grain and seed at the start of their crop cycle, but have a surplus after harvest. An entity that is able to bridge this gap is required. In Sumer, that entity was the temples. Farmers and merchants deposited excess grain and silver with the priests after a harvest to be kept safe. These were then lent to other farmers who needed these for their own farms. When those farmers were able to harvest their own crops, the priests took back what was lent, with interest.
Every element of this arrangement arose directly from a practical constraint. Deposits and loans existed because the timing mismatch was real. Interest existed because lenders committed their resources over time and took on risk; without a return, no one would be willing to lend. Records – cuneiform markings on clay tablets – existed because strangers could not rely on memory and trust alone. By the 18th century BCE, the Code of Hammurabi had enshrined this system in law: a statutory interest rate of 20% on silver loans and 33.3% on barley loans. Pricing different risks differently was already institutionalised four thousand years ago.
This innovation was one of the most important for two reasons. First, it tackled the fundamental problem of mismatched needs and resources across time, something no agricultural society could avoid. Second, it emerged independently, again and again. Deposits, loans and interest appeared not only in Sumer but also in ancient Egypt, India, China, Greece, and Rome. Every civilisation that independently developed cities and agriculture developed lending and interest, without exception.
Distance: bills of exchange
The next wall to be bridged was distance. Often people will find that their money and what they wish to trade for are in different cities, and the roads are crawling with bandits.
The solution was to keep the money still and move only the records of it. In the 12th century the Knights Templar – a military religious order – let pilgrims deposit silver in London, and withdraw it in Jerusalem with a coded letter of credit. A thief who seized the parchment could do nothing with it. At almost the same time, Italian merchants developed the bill of exchange: pay in Florence, take a slip of paper, redeem it for local coin in Bruges.
The function was inevitable. Transferring value across distances without moving physical money was a fundamental need for commerce. And similar solutions emerged independently in places that had no contact with one another – the Islamic world’s hawala remittance network grew from the same constraint with no shared ancestry, and still runs worldwide today.
Weight: paper money
The next wall: Weight. More specifically, the physical weight of currency. During the Northern Song dynasty, iron coins were used in Sichuan. A thousand coins weighed about 12.5 kilograms, and a single bolt of silk cost forty-five to fifty kilograms of coins, an impractical trade. The costs of trading became so absurd that innovation became a necessity.
The answer was paper. Merchants in Chengdu issued deposit receipts known as jiaozi. These could be presented to withdraw coins. Later these receipts were standardised, and eventually became the currency itself. After private operators issued too many of these Jiaozi, the Song court took it over in 1023, backed it with a reserve, and issued the world’s first government paper money – about six centuries before Europe’s earliest banknote.
Europe did not simply copy paper money from China. When Marco Polo encountered “money made from tree bark” in Yuan China, he was astonished – a sign of how unfamiliar the mechanism was to Europeans at the time. Six hundred years after China’s innovation, Europe independently reinvented paper money in response to its own metal shortages, unaware of the earlier solution. The same constraint – metal’s lack of portability – produced the same solution in East and West, centuries apart and without either drawing on the other.
Keeping count: double-entry bookkeeping
When metal is scarce and much trade runs on credit, a technical but fatal problem appears: who owes whom how much, and how do you prevent errors and embezzlement? The system at the time was not suitable for keeping track of the complex network of debts and claims.
The solution was double-entry bookkeeping – every transaction recorded twice, as a debit and a credit, and they must balance. Any error shows at once. Florentine merchants were using it by the late 13th century, and in 1494 the Franciscan friar Luca Pacioli wrote it into a mathematics textbook that the printing press carried across Europe.
The function was necessary. Credit trade has to track its debts.
Risk: the joint-stock company
Ocean-going trade brought the risk wall: concentrated risk. Ships can sink, cargo can be seized, crews can die, and the odds of losing everything on one voyage are high. No single merchant dares stake his whole fortune on one hull. The answer is to cut a ship’s risk into many shares, each carrying a portion of risk and profits. The Dutch East India Company (VOC) brought this to full form in 1602: Permanent capital (money that stayed in the company rather than dissolved after each voyage), freely transferable shares, and a secondary market where shares can be traded at any time.
This is the step with the richest evidence of convergent evolution. Pooled capital with shared risk grew up independently, centuries apart, in places with no contact: Rome’s tax-farming companies, whose shares could be bought and inherited; and Sweden’s Stora Kopparberg copper mine, which left one of the earliest known share certificates in 1288. The VOC’s greatness was not invention but assembly – the first to put permanent capital, transferable shares and a secondary market in one place.
Catastrophe: insurance
Insurance shares the risk of a disaster by spreading the risk across a crowd. The idea is old: the Phoenicians were already pledging ship and cargo as security around 1200 BC, forgiven if the ship went down, and the earliest written marine-insurance contracts appear in the 14th-century Italian city-states.
But the memorable form is Lloyd’s coffee house in London, which no government designed: from the 1680s, underwriters gathered at Lloyd’s to share shipping news and took on each other’s risks. Over time it grew into the most important insurance market on earth.
Spreading catastrophic losses across a group was a fundamental need. No individual would have been able to brave the oceans otherwise, and intercontinental trade would have suffered as a result. The fact that it occurred multiple times across time and countries solidifies the proof.
War: government bonds and central banks
The next wall is war. More specifically, it is the fact that the cost of war far outstrips what a government can collect in taxes. It has to borrow. This leads to the development of government bonds.
Venice and Florence were using transferable public debt to fund wars in the 14th century, but the real leap came in London in 1694. England was locked in war with France, and the Crown’s credit was too poor to borrow cheaply. A Scottish financier, William Paterson, proposed a joint-stock bank: merchants would pool £1.2 million and lend it to the Crown in exchange for the right to issue banknotes. This led to the formation of the Bank of England – an emergency measure for war finance that invented the template of the modern central bank.
Nearly every early central bank was forced out the same way, and the sharpest evidence is the counter-example: France built no comparable, trustworthy public-credit institution, and its slide through one fiscal crisis after another to bankruptcy was among the triggers of the 1789 revolution. What made a government’s debt cheap was never the gold in its vaults but its record of paying on time – which is why Spain, sitting on mountains of New World silver but defaulting four times, borrowed more dearly than the Dutch, who had no silver at all.
An uncertain price: futures
Uncertain future prices was the next wall. Farmers fear grain prices will crash at harvest time; buyers fear prices will soar when supplies run low. This led to the necessary innovation of standardised future contracts.
Japan turned it into an institution at the Dojima rice market in Osaka in 1730. Samurai were paid their stipends in rice; the rice was issued as transferable warehouse receipts, and merchants could go long or short on a harvest not yet in by putting down only a margin. Dojima had membership, clearing and uniform contract terms – standard delivery units, minimum price moves, delivery grades, expiry dates, cash settlement – and is generally reckoned the world’s first organised futures exchange, about a century and a half before Chicago. Its independence is especially clean: it grew entirely inside Japan, with no Western contact, yet arrived at almost exactly the institutional details futures trading uses today.
The reserve-currency trap: from gold to fiat
By the late 19th century, most major economies were on the gold standard: currency pegged to gold, notes in theory redeemable for it. This system offered stability, but had a fundamental flaw.
The post-war Bretton Woods arrangement exposed this flaw. The dollar was pegged to gold at $35 an ounce, and other currencies pegged to the dollar. In 1960, the Triffin dilemma was identified: World trade was growing, more dollars were required to serve abroad as reserves; but the more dollars were supplied, the less gold was available to cover them. This led to the dollar’s convertibility becoming weaker as global confidence dropped. Either the United States tightened the dollar and starved global trade, or it kept the taps open until confidence broke. The system was built to self-destruct.
As foreseen, America’s gold drained away. By 1971, the reserve was about $10 billion against more than $70 billion in dollar claims abroad. This led to Nixon suspending the dollar’s convertibility into gold on 15 August 1971, and the age of pure fiat currency began.
The structure was necessary – as long as one national currency served as the global reserve currency while remaining tied to a finite supply of gold, the Triffin dilemma had no solution. This leads into the next wall humanity faced.
Trust again: digital currency
Under fiat money, value rests not on gold but on trust in central banks and the banking system. That trust cracked in 2008 during the global financial crisis. Excessive risk-taking by major banks nearly brought down the entire financial system, leaving governments and taxpayers to fund the rescue. Some people began questioning the very premise that financial intermediaries had to be trusted.
In January 2009, Satoshi Nakamoto created the first bitcoin. Its objective was to replace the requirement to trust banks with a system that used cryptography and distributed bookkeeping to establish trust between strangers, without relying on any intermediary.
The need was necessary; its form was contingent. Building trust between strangers without depending on a middleman who might fail is the oldest problem there is. The Sumerian temple, double-entry, and the Bank of England were all mechanisms for solving this problem. But that it took this particular technology, ignited at this particular moment after 2008, launched by an anonymous figure in this way, depended entirely on the technical conditions and the mood of the time. The technology moved from clay tablet to blockchain, but the problem it resolved was the same as the one 4,000 years ago.
The map
Finance did not grow along a random path but along one pushed, again and again, by the same four walls:
- Time → deposits, loans and interest
- Distance → bills of exchange
- The weight of metal → paper money
- Credit-account tracking → double-entry bookkeeping
- Concentrated risk → the joint-stock company (reinvented in many places)
- Catastrophic loss → insurance (necessary; the path an accident)
- War spending → government bonds and central banks
- Price swings → futures (East and West converging)
- The reserve-currency trap → fiat money (structure necessary; timing an accident)
- A crisis of trust in intermediaries → digital currency (the need necessary; the form an accident)
Three judgements stand out from this map.
First, the main line is necessary and the details are accidents: each wall is real, so the tool to breach it arrives sooner or later, but which city produces it first is history’s coin-toss.
Second, independent recurrence is the best test of a real need – deposits, paper money, the share and the futures contract all grew separately in civilisations out of contact, while an innovation that stands up only in one place, on one story, and is never reinvented elsewhere deserves a second look.
Third, and most counter-intuitive: the more an innovation looks epoch-making, the more likely it is only an old need in new clothes. Bitcoin is called a revolution, but it solves the trust problem the Sumerian temple was already solving; in AD 33, the Roman emperor Tiberius did what we now call quantitative easing, injecting public, interest-free liquidity to thaw a frozen credit market.
The carriers change, from clay to gold to paper to servers, but the problems have not changed by a word in five thousand years.
How the walls still hit you today
None of these walls has fallen. Each one presses on your own money, usually where you least notice it:
- Time. Compound interest sits on both sides of the ledger. It rolls a modest monthly savings habit into a real sum over decades, and rolls a credit-card balance up just as fast the other way. What Sumerians understood four thousand years ago, many adults still learn the hard way.
- Distance. You no longer carry cash over the mountains, but the cost of moving value across distance never vanished; it went into hiding. Wire money across borders, and the exchange-rate spread and fees the banks skim off are the modern form of the interest that old bill of exchange hid inside its rates.
- Weight, now inflation. The Song note losing value fast and your bank balance losing value slowly work by an identical mechanism – a silent tax you neither vote for nor can opt out of. Which is why the first question to ask of any place you put money is not “what percent did it return” but “did it beat inflation”.
- Risk. Cutting one ship’s risk into many shares is, in today’s words, not putting your fortune in one basket. An index fund does what the Dutch did: it makes you a small shareholder in hundreds of companies, so no single failure breaks you. Diversification allows you to lower risk at no extra cost.
- Catastrophe. Most people get insurance backwards: they leave the big risks uncovered – critical illness, life, family liability – and buy a pile of complicated bundled “protection-plus-savings” products. Insurance was born to move a risk you cannot bear for a small sum, not to breed money.
- War, now your credit record. What made a state’s debt cheap – its record of paying on time – works on you. The credit record a bank checks for a mortgage or card is your personal version of sovereign credit. A Spanish king who defaulted four times paid over 10% interest; a few missed payments cost you just as concretely.
- Price, now leverage. A Dojima merchant controlling a whole batch of rice on a margin was using leverage – a small sum moving a large asset. Your mortgage is leverage too. But it magnifies losses as well as gains, and every blow-up in history has the same script: leverage meeting a sudden drought of liquidity.
- Trust. Trust is finance’s most central and most fragile thing, which is exactly why fraud loves it – Ponzi schemes, high-yield “wealth products,” guaranteed-return crypto, romance scams. The charm against being fooled is nearly universal: anything that promises high returns, low risk and steady payouts all at once is almost certainly a fraud, because in the real world high return and low risk are opposites.
The tools keep changing their names – a temple loan, a bill of exchange, an index fund, a blockchain – but behind each one is a farmer, a merchant or a saver trying to get past the same four walls. See the wall behind the tool, and finance stops being something that happens to you and becomes something you can read.
Previously in this series: What would humans do when work is no longer needed?
Next in this series: Why do poor people need to understand finance more than the rich?
