3: Introduction to Traditional Finance
Introduction
Understanding decentralized finance (DeFi) requires a solid grasp of the traditional financial system it seeks to reimagine. This chapter examines how the conventional financial system operates—from the creation of money to the execution of trades—providing the essential context for understanding DeFi's innovations and the problems it addresses.
Traditional finance evolved over centuries to solve fundamental economic challenges: how to allocate resources efficiently across time and risk. The current system accomplishes this through a complex web of institutions, intermediaries, and markets, each playing specific roles in facilitating transactions, managing risk, and enabling economic activity.
1. The Core Problem: Resource Allocation
1.1 The Fundamental Challenge
Finance exists to solve a deceptively simple problem: how to allocate resources efficiently across time and risk. This manifests in two primary contexts:
Personal Investment:
- Building wealth over time
- Saving for retirement
- Insuring against adverse events
- Managing consumption smoothing (spending today vs. saving for tomorrow)
Business Investment:
- Funding new projects and ventures
- Managing working capital
- Hedging operational risks
- Accessing growth capital
Financial markets and contracts enable both individuals and businesses to achieve these goals by facilitating the transfer of resources between those who have excess capital and those who need it.
1.2 Measuring Success: Return and Risk
Any financial system must provide tools to evaluate investments:
Return Measurement:
Return = (Ending Value - Initial Investment) / Initial Investment × 100%
For example:
- Invest $100, receive $150: Return = 50%
- Invest $100, receive $75: Return = -25%
Risk Measurement: Risk is typically measured by the standard deviation of returns, representing the uncertainty or variability in outcomes. A simple illustration:
| Scenario | Probability | Outcome | Return |
|---|---|---|---|
| Good Economy | 50% | $200 | 100% |
| Bad Economy | 50% | $50 | -50% |
Expected Return = (0.5 × 100%) + (0.5 × -50%) = 25%
The wide range of possible outcomes (from -50% to +100%) represents significant risk.
1.3 The Concept of Efficiency
Efficiency in financial markets has multiple dimensions:
- Allocative Efficiency: Resources flow to their highest-value uses
- Operational Efficiency: Transaction costs are minimized
- Informational Efficiency: Prices reflect all available information
A well-functioning financial system ensures that:
- Goods are allocated to people who value them most
- People willingly participate in the system
- Spillover risks (externalities) are properly managed
2. Money in the Modern Economy
2.1 What is Money?
Money is not simply coins and bills—it's fundamentally a special kind of IOU (I Owe You) that everyone in an economy trusts and accepts. This trust makes money universally acceptable as a medium of exchange.
The Three Functions of Money:
-
Store of Value: Money should retain its purchasing power over time. Gold mined centuries ago remains valuable today, while perishable food quickly becomes worthless.
-
Unit of Account: Money provides a common measure for pricing goods and services. In modern economies, prices are quoted in currency (dollars, euros, pounds) rather than in terms of other goods.
-
Medium of Exchange: Money is something people hold specifically to exchange for other things, not for its intrinsic value. For example, in POW camps during WWII, cigarettes became money—even non-smokers held them to trade for desired goods.
These functions are interdependent: money works as a medium of exchange precisely because it's a reliable store of value. If a currency experiences hyperinflation (as Germany did in the 1920s, when prices doubled 38 times in five years), people abandon it for more stable alternatives.
2.2 Types of Money in Modern Economies
Three distinct types of money circulate in contemporary economies, each representing IOUs between different sectors:
2.2.1 Physical Currency (Fiat Money)
What it is:
- Banknotes and coins
- An IOU from the central bank to the holder
- Represents about 3% of broad money in modern economies
Historical evolution: Originally, banknotes were convertible to gold—a system called the "gold standard." The Bank of England, for instance, would exchange gold for its notes on demand. However, most countries abandoned this system in the 20th century. Britain permanently left the gold standard in 1931, allowing better control of the money supply during the Great Depression.
Modern fiat money: Since abandoning gold convertibility, modern currency is "fiat" money—valuable by government decree rather than backing by commodities. This offers crucial advantages:
- Central banks can adjust money supply to economic conditions
- No artificial constraints from gold mining rates
- Better ability to respond to crises
Why people accept fiat money:
- Government acceptance: The government accepts it for tax payments
- Legal tender laws: It's designated as official currency
- Stability commitment: Central banks target low, stable inflation (typically 2%)
- Social convention: Everyone else accepts it, creating a self-reinforcing system
2.2.2 Bank Deposits (Commercial Bank Money)
What they are:
- Electronic records of amounts owed by commercial banks to customers
- IOUs from commercial banks to households and businesses
- Represent about 97% of broad money
Why they're preferred:
- Security: Safer than holding large amounts of cash
- Interest: Deposits often earn interest; cash doesn't
- Convenience: Electronic transfers are easier than physical currency
- FDIC protection: Deposits are often insured (up to limits)
How they function: When you deposit $1,000 in a bank:
- The bank credits your account with $1,000 (their IOU to you)
- You can use these deposits to make payments
- Payments transfer IOUs between accounts without moving physical cash
Modern payments increasingly use bank deposits directly as the medium of exchange—when you pay by card or bank transfer, you're transferring bank IOUs, not currency.
2.2.3 Central Bank Reserves
What they are:
- Electronic IOUs from the central bank to commercial banks
- The "banker's bank account"
- Not directly accessible to the public
Their purpose: Commercial banks use reserves for:
- Settling payments between banks
- Meeting withdrawal demands
- Satisfying regulatory requirements
- Obtaining physical currency when needed
Example of reserves in action: When Bank A's customer pays Bank B's customer:
- Customer A's deposit at Bank A decreases
- Customer B's deposit at Bank B increases
- Bank A transfers reserves to Bank B to settle
- The central bank adjusts reserve account balances
2.3 The Banking System and Money Creation
2.3.1 How Banks Create Money
One of the most misunderstood aspects of modern finance is that commercial banks create money when they make loans—they don't simply lend out existing deposits.
The conventional (wrong) understanding:
- Savers deposit money in banks
- Banks lend out those deposits
- The money supply is constrained by deposits
How it actually works:
- A bank approves a loan (e.g., $300,000 mortgage)
- The bank credits the borrower's account with $300,000
- New money has been created: The borrower has new deposits; no one else's deposits decreased
- The borrower's debt to the bank is the offsetting liability
Before Loan: After Loan:
Bank Assets: $0 Bank Assets: $300,000 (loan)
Bank Liabilities: $0 Bank Liabilities: $300,000 (deposit)
Borrower Assets: $0 Borrower Assets: $300,000 (deposit)
Borrower Liabilities: $0 Borrower Liabilities: $300,000 (loan)
This process is sometimes called "fountain pen money"—created at the stroke of a pen when banks approve loans.
2.3.2 Money Destruction
Just as loans create money, loan repayment destroys money:
Example: You spend $10,000 on a credit card during the month:
- Your outstanding debt increases by $10,000
- Merchants' deposits increase by $10,000
- Money has been created
When you pay off the credit card:
- Your deposits decrease by $10,000
- Your debt decreases by $10,000
- Money has been destroyed
2.3.3 The Money Multiplier Myth
Traditional textbooks often describe a "money multiplier" where central banks control money supply by adjusting reserves. This is not accurate for modern economies.
The myth:
- Central banks set the quantity of reserves
- Banks "multiply up" reserves through lending
- Reserves are a binding constraint on lending
The reality:
- Central banks set the price of reserves (interest rates)
- Banks decide how much to lend based on profitable opportunities
- Banks' demand for reserves follows from their lending decisions
- The relationship operates in reverse: lending creates deposits, which then determine reserve needs
2.4 The Payment System
2.4.1 The Cost of Payments
Processing payments is expensive—estimates suggest it costs approximately 3% of GDP in the United States. Consumers often don't see these costs directly, but they're embedded in the system through:
- Merchant fees (typically 2-3% for credit cards)
- Interchange fees between banks
- Fraud prevention costs
- Infrastructure maintenance
2.4.2 Payment Methods and Their Characteristics
Different payment methods offer varying combinations of speed, finality, and cost:
| Method | Speed | Finality | Cost | Risk |
|---|---|---|---|---|
| Cash | Instant | Immediate | Low | Theft/loss |
| Debit Card | 1-2 days | T+1 | Medium | Fraud |
| Credit Card | 30+ days | T+30+ | High | Chargeback |
| Wire Transfer | Same day | Immediate | High | Rare |
| ACH | 1-3 days | T+1 to T+3 | Low | Error |