What is Money? And Why Bitcoin Changes the Answer

What Is Money?

Most people use money every day without ever asking what it actually is. We earn it, save it, spend it, borrow it and invest it. Entire careers are built around making more of it.

But when you ask a more fundamental question “what makes something money?”, the answer becomes less obvious. Understanding Bitcoin starts here, not with blockchain, nodes, mining or price, but with money itself.

The Problem Before Money Existed

Before money existed, trade was difficult. Imagine a world without it. You grow wheat and want a pair of shoes, but to make that trade you need to find someone who makes shoes and also happens to want wheat.

If the shoemaker does not want wheat, the trade cannot happen. Perhaps they want meat instead. You now need to find someone who has meat and wants wheat, exchange your wheat for their meat, and then take that meat to the shoemaker.

But what if the person selling meat also does not need wheat? The problem quickly becomes obvious. For direct trade to work, two people need to possess exactly what the other person wants at roughly the same time.

Economists describe this as the double coincidence of wants. It sounds technical, but the idea is simple: I need to want what you have, and you need to want what I have. Without that coincidence, trade becomes inefficient.

There are other problems as well. What if you own a cow and you want to buy a loaf of bread? You cannot easily divide the cow without destroying much of its value. What if the goods you produce are seasonal, or they go off before you find someone else willing to trade?

What if you want to save the value of today’s work for use several years from now? Barter struggles with all of these problems. As societies became larger and more specialised, direct exchange became impractical.

Why Money Emerged

A farmer might produce food, a builder constructs houses, a doctor provides medical care and a shoemaker makes shoes. For a sophisticated economy to develop, people needed something that could sit between every transaction, something almost everyone would accept, even if they had no immediate use for it. That something became money.

Instead of wheat being exchanged directly for shoes, the farmer could first exchange wheat for money and then use that money to buy shoes. The farmer no longer needed to find a shoemaker who wanted wheat. They only needed to find someone willing to buy the wheat for money. The shoemaker, meanwhile, could accept the same money and later spend it on whatever they needed.

Money therefore solved one of the most important problems in economic history. It separated the act of selling from the act of buying. This dramatically increased the number of possible trades between people and allowed individuals to specialise in what they were good at, knowing that the value they created could be exchanged for something universally accepted. That is one of the reasons money became such a powerful technology.

The Three Functions of Money

Once money becomes the bridge between transactions, it begins performing three important functions.

The first is that it acts as a medium of exchange, allowing us to buy and sell without directly swapping goods and services. Instead of constantly searching for someone who wants exactly what we have, we exchange our work or goods for something broadly accepted by everybody else.

The second is that it acts as a unit of account, giving us a common language for prices. A house might cost £500,000 and a coffee might cost £4, and we do not need to calculate how many coffees a house is worth or how many hours of labour equal one car. Everything can be measured against the same unit, which makes economic calculation dramatically easier.

The third is that it acts as a store of value, allowing purchasing power to move through time. You can work today, save the proceeds and spend them later. This final function is particularly important because money is not just a technology for exchanging value, but also a technology for storing human time and effort. If you work for a month and save part of your salary, that money represents hours of your life that you chose not to consume immediately. Good money should allow you to carry that value into the future.

What Makes Good Money?

Throughout history, societies have used many things as money, including shells, beads, livestock, silver, gold and paper notes. But some forms of money worked better than others. The strongest forms tended to share certain characteristics.

They were scarce, durable, portable, divisible, fungible, verifiable and acceptable.

Money is ultimately a competition between different technologies for storing and transferring value, and for thousands of years gold was one of the strongest technologies humanity found.

Why Gold Became Money

Gold became money because it has many of the characteristics we want. It is scarce, cannot easily be manufactured, lasts almost indefinitely and is divisible. Because producing additional gold requires significant energy, labour and capital, its supply cannot suddenly be increased at will. That scarcity mattered because it meant that holding gold did not automatically dilute your share of the total supply.

However, gold also has weaknesses. It is heavy, difficult and expensive to transport in large quantities, and hard to verify quickly. As economies became increasingly global, moving physical gold around the world became impractical, so we began using representations of gold instead, in the form of paper.

From Gold to Fiat Money

For long periods, banknotes represented claims on gold held elsewhere. Instead of carrying metal, people carried paper that could theoretically be exchanged for it. Over time, however, most major currencies stopped being directly redeemable for gold. Today’s pounds, dollars, euros and yen are known as fiat currencies.

Their value doesn’t come from being redeemable for a scarce commodity, but from the monetary system surrounding them, including governments, central banks, commercial banks, laws, taxation and widespread acceptance.

Fiat money solved some of gold’s problems extraordinarily well, particularly through digital banking, which allows value to move across the world almost instantly, and through credit systems that finance businesses, homes and governments. Central banks can also respond to financial crises.

However, the system introduced a different characteristic: the money supply can be expanded. That has consequences.

Inflation And the Cost of Expanding Money

If an economy contains a fixed amount of money and your share of it is known, an increase in the total supply reduces your share even if your nominal balance does not change. In real economies this is more complex, and increases in money supply do not translate mechanically into price increases, but the principle still matters.

When new money is created, it does not arrive evenly. It enters the system through specific channels such as banks, governments, financial markets and is spent by certain actors before others have access to it.

Those closest to the source of new money can spend it at yesterday’s prices, while those further away face rising costs before their incomes adjust. This uneven distribution is often referred to as the “Cantillon effect”.

If the quantity of money grows faster than the goods and services people want to buy, the purchasing power of each unit of money can decline. We experience that as inflation. But inflation is not just a change in prices, it’s a gradual transfer of purchasing power from savers to early recipients of new money.

This creates an unusual characteristic of modern money, where saving money often means accepting that it will buy less over long periods of time. In effect, holding cash becomes a slow leak on your stored time and energy.

That changes behaviour. People are encouraged to invest not only to grow wealth, but to preserve it. Businesses seek assets that can keep pace with monetary expansion. Pension funds take on more risk to maintain real returns. Households buy property, equities, or other stores of value, often not simply to become wealthier, but to avoid becoming poorer in real terms.

In this sense, expanding money supply does more than adjust prices. It reshapes incentives, redistributes purchasing power, and quietly influences how people choose to store the value of their time.

Bitcoin & the Idea of Absolute Scarcity

Bitcoin introduced a different question: what if money itself were scarce?

Launched in 2009, Bitcoin has a maximum supply of 21 million units, enforced by the rules of the network rather than by any government or central bank. New bitcoin enters circulation through mining, but approximately every four years the rate of issuance is cut in half, eventually approaching zero.

The important point is not just that Bitcoin is scarce, but that its scarcity is known in advance. Nobody can create more of it, and nobody can change that limit.

Bitcoin therefore combines characteristics that previously existed separately. Gold is scarce but difficult to move. Fiat currencies are easy to move but not scarce. Bitcoin attempts to combine both.

It’s scarce, portable, divisible, verifiable, durable and global. This is why describing Bitcoin simply as a cryptocurrency misses much of the point. Its most important innovation is not digital payments, but digital scarcity.

Why Scarcity Matters

Scarcity matters because it forces economic trade-offs. If something can be produced infinitely (like fiat currencies can be by central banks), holding it over time becomes difficult because future supply may dilute existing holders. A fixed supply changes that dynamic.

As more people choose to hold Bitcoin, they compete for ownership of a finite asset. This does not guarantee price appreciation, since demand can fall and markets can behave unpredictably, but the supply side is unusually predictable. At any point in the future, the number of Bitcoin that will exist can be estimated with remarkable accuracy, which is fundamentally different from all other monetary assets.

Why Bitcoin is Easier to Understand from First Principles

One of the biggest mistakes people make when trying to understand Bitcoin is starting with the technology. They hear about mining, private keys, blockchains, wallets and nodes and the subject immediately feels complicated.

But Bitcoin makes far more sense when you begin with a simpler question: what is money? Why do we need it? What makes one form of money better than another? Why has gold remained valuable for thousands of years? Why does modern money lose purchasing power? And what would happen if a monetary asset existed that was digital, global and absolutely scarce?

Once you understand those questions, Bitcoin becomes easier to understand.

What Bitcoin Actually Represents

Bitcoin’s not simply a new asset competing for investment capital, but an attempt to answer one of humanity’s oldest economic questions: what’s the best way to preserve and transfer value through time?

For centuries, the answer evolved from commodities to precious metals, from gold-backed paper to fiat currencies and digital bank balances.

Bitcoin introduces another possibility: a monetary network without a central issuer, a digital asset without unlimited supply and a form of money whose rules cannot easily be changed by the people who control it.

You don’t need to believe Bitcoin will replace today’s monetary system to understand why that matters. But to understand Bitcoin properly, you first need to understand the problem it was designed to solve. And that problem begins with money.