Money has no value of its own. It works only because we all agree to believe in it.

Part 2

How Money Really Works

The machine under the hood — where money comes from, and the trick that lets banks create it.

6How a bank really works
7Fractional reserve banking
8Who makes money
9Inflation & interest rates
10Crypto & digital money
11Bubbles & manias

How a bank really works

A bank isn't a vault. It's a machine for turning your savings into other people's loans.

You think the bank guards your money. Really, it borrows from you (your deposit) and lends to others at a higher rate. The gap between the interest it pays you and the interest it charges borrowers — the spread — is how it makes its money.

Where the bank's profit comes from

It pays savers a little, charges borrowers more, and keeps the difference. Profit = 6% charged − 1% paid = the spread.

The spread

6% − 1%

Pays you a little, charges borrowers more, pockets the gap.

The danger

A bank run

If everyone wants their cash at once, the bank can't pay — it lent it out.

The one number

~$1.4trillion

Held between Singapore's three big banks — DBS, OCBC and UOB — combined.

A bank is a place that will lend you money if you can prove that you don't need it.

Bob Hope

Fractional reserve banking

The quiet trick at the heart of the whole system: banks lend out most of what you deposit — and that act creates brand-new money.

Put $1,000 in the bank and you assume it sits in a vault. It doesn't. The bank keeps a small slice as a reserve and lends the rest. The borrower spends it, it lands in another bank, which keeps a slice and lends the rest again. Round after round, your single $1,000 becomes many times that.

How $1,000 becomes ~$10,000

Each round the bank keeps 10% (navy) and lends the rest (green). Every loan becomes the next deposit — watch the running total climb.

The punchline

$1,000 of cash → ~$10,000 of money

Real cash in reserve$1,000

New money created~$9,000

The reserve

10%

kept by the bank. The smaller the reserve, the more money the system creates.

The multiplier

×10

every $1 of real cash can support about $10 of money in the economy.

The process by which banks create money is so simple that the mind is repelled.

John Kenneth Galbraith, economist

Who makes money

Above all the banks sits one institution that can create — or destroy — money on purpose.

A central bank is the bank for banks. It controls how much money exists, sets the cost of borrowing, and rescues the system in a crisis. Singapore's is the Monetary Authority of Singapore (MAS) — unusually, it steers the economy through the exchange rate, not interest rates.

The money pyramid

Lender of last resort

The backstop

In a panic, the central bank steps in so the system doesn't collapse.

MAS is different

The dollar

It steers the economy via the SGD exchange rate, not interest rates.

Inflation is always and everywhere a monetary phenomenon.

Milton Friedman, economist

Inflation & interest rates

Two dials run the whole economy — and they're wired together.

Inflation is prices rising over time, so each dollar buys less. Central banks fight it with interest rates: raise rates and borrowing gets dearer, spending cools, prices settle. Cut rates and the opposite happens. It's a constant balancing act.

The balancing act

The Rule of 72 — pick an inflation rate

At this rate, prices double in about 12 years.

72 ÷ 6 = 12

Inflation is when you pay fifteen dollars for the ten-dollar haircut you used to get for five dollars.

Sam Ewing, writer

Crypto & digital money

A new kind of money that no single bank or government controls.

Cryptocurrency is digital money recorded on a blockchain — a shared ledger copied across thousands of computers, so no single bank or state runs it. Bitcoin was the first, in 2009. Supporters love the freedom; critics point to wild price swings and scams.

How a blockchain works

No middleman — a network of computers agrees on every transaction.

No middleman

No bank

The network — not a company — keeps the record honest.

The catch

Wild swings

Prices can soar and crash; scams are common. Tread carefully.

Top 5 cryptocurrencies by value

Ranked by market value, late 2025 (approximate). Bars drawn to scale — Bitcoin is worth more than the next four combined.

The root problem with conventional currency is all the trust that's required to make it work.

Satoshi Nakamoto, creator of Bitcoin

Bubbles & manias

Every so often, crowds convince themselves something is worth far more than it is.

A bubble is when a price soars far above real value because everyone's buying simply because the price is rising — until belief snaps and it crashes. From Dutch tulips in the 1600s to dot-com stocks and crypto, the pattern repeats: greed, mania, crash, regret.

The shape of every bubble

Smart money quietly buys early; the crowd piles in at the top.

The tell

Everyone's in

When people who never invest start buying, the new buyers are about to run out.

What pops it

No new buyers

Prices only rise while fresh money keeps arriving. It always stops.

Insider tell

Bubbles don't burst on bad news. They burst the moment there's no one left to buy — when the last optimist has already bought in.

The four most dangerous words in investing are: 'this time it's different.'

Sir John Templeton, investor