Nature of Economics

Economics is the study of how scarce resources are allocated to satisfy unlimited human wants. This sub-theme sets up the core ideas — scarcity, choice, opportunity cost and the way economists think — that everything else in the course is built on.

Learning objectives — by the end of 1.1 you can…

- explain scarcity, choice and opportunity cost, and why economics is a social science; - tell positive from normative statements and explain the role of value judgements; - draw and interpret a PPF, including shifts, and the capital vs consumer goods trade-off; - evaluate specialisation and the division of labour, and the functions of money; - compare free-market, command and mixed economies.

1.1.1 Economics as a social science

Economics is a social science: it studies human behaviour using the methods of science. Economists observe behaviour, build a hypothesis, construct a model, then test it against real-world evidence — the same broad approach a physicist uses, but applied to people.

The catch is that you cannot run a controlled lab experiment on a whole economy. So economists rely on models — deliberate simplifications of reality that isolate the key relationships. To make a model work, we hold everything else constant.

Key Terms

Ceteris paribus — Latin for "all other things being equal." It lets economists isolate the effect of one variable by assuming nothing else changes. e.g. "If the price of coffee rises, quantity demanded falls — ceteris paribus."

Economic model — A simplified representation of reality used to explain and predict behaviour.

Economics is usually split into two branches, and Theme 1 sits firmly in the first:

The two branches of economics

Microeconomics — The study of individual markets and the decisions of households and firms — prices, demand, supply, a single industry. (This is the whole of Theme 1.)

Macroeconomics — The study of the economy as a whole — growth, inflation, unemployment, the actions of government. (This is Theme 2.)

The two overlap constantly: a microeconomic event (a spike in the oil price) quickly becomes a macroeconomic problem (higher inflation).

"Thinking like an economist" means three habits: weighing up costs against benefits at the margin (the effect of one more unit), being clear about your assumptions, and separating what is from what you think ought to be — which leads us neatly to the next point.

1.1.2 Positive & normative statements

Distinguishing these two is a guaranteed exam skill.

Value judgements shape economic decisions and policy. Two economists can agree on the facts yet disagree on policy because they hold different values about what is desirable — which is why economics is rarely settled by evidence alone.

Watch Out

A positive statement does not have to be correct — it just has to be testable. "The Earth is flat" is a (false) positive statement. Don't confuse "positive" with "good."

1.1.3 The economic problem

The fundamental economic problem is scarcity: resources are finite, but human wants are infinite. Because we cannot have everything, we must choose — and every choice has a cost.

The resources used to produce goods and services are the factors of production:

Resources can be renewable (replenish naturally, e.g. solar, fish stocks if managed) or non-renewable (finite, e.g. oil, coal). This leads to three questions every economy must answer: What to produce? How to produce it? For whom to produce?

Key Terms

Opportunity cost — The value of the next best alternative forgone when a choice is made. It applies to consumers (spend £40 on a game = forgo a meal out), firms, and governments (spend on the NHS = less for defence).

Economic good — A good that is scarce and therefore has an opportunity cost.

Free good — A good with no opportunity cost because it is not scarce (rare in reality — sometimes air, sunlight).

1.1.4 Production possibility frontiers (PPF)

A PPF shows the maximum combinations of two goods (or two types of good) an economy can produce when all its resources are used fully and efficiently, with a given level of technology.

The curve is concave to the origin (bowed outward) because of increasing opportunity cost: factors of production are not equally suited to making both goods, so as you switch more resources to one good, you give up ever-larger amounts of the other.

#### Choosing between capital and consumer goods

One of the most important trade-offs a PPF shows is between making capital goods (machines, factories — things that help future production) and consumer goods (things to enjoy now). Devote more resources to capital goods today and you sacrifice present consumption — but you invest in the economy's ability to grow.

#### Shifts vs movements

A movement along the PPF is just a reallocation of existing resources (a change in opportunity cost). A shift of the whole PPF changes the economy's productive potential:

Exam Tip

The capital vs consumer goods trade-off is a favourite. Choosing more capital goods today (investment) lowers current consumption but shifts the PPF further out in the future — short-term sacrifice for long-term growth. Always label your axes and show the shift with a clear arrow.

1.1.5 Specialisation & the division of labour

Specialisation is when individuals, firms, regions or countries concentrate on producing a particular good, service or task. The division of labour is a type of specialisation where the production process is broken into separate tasks, each performed by a different worker.

Real World — Adam Smith's pin factory

In The Wealth of Nations (1776), Adam Smith described a pin factory where ten workers each doing one task (drawing wire, cutting, sharpening…) could make tens of thousands of pins a day — vastly more than if each worker made whole pins alone. This is the power of the division of labour.

The same logic scales up to specialisation and trade between countries: nations specialise in what they are relatively best at, then trade. This widens choice, lowers prices and allows economies of scale — but creates over-dependence, risks if world demand falls, and can deplete a country's resources.

#### The functions of money

Specialisation only works if people can exchange what they produce — which requires money (barter is too clumsy). Money has four functions:

1. Medium of exchange — accepted for buying and selling, removing the need to barter.
2. Measure of value (unit of account) — lets us put a price on everything and compare.
3. Store of value — holds its worth over time, so you can save.
4. Method of deferred payment — allows borrowing and lending (paying later).

1.1.6 Free market, mixed & command economies

Economic systems differ in who owns resources and who answers the "what / how / for whom" questions.

Evaluation — the role of the state

No economy is purely free or purely planned; the real debate is how much government. Hayek argued central planners can never gather enough information to allocate resources as well as millions of decentralised price signals. The counter-view is that pure markets fail — they ignore pollution, under-supply public goods and widen inequality — so the state must step in to provide public goods, correct market failure, redistribute income and regulate.

Real World — systems on a spectrum

No country sits at the extremes. Hong Kong and Singapore lie towards the free-market end (low tax, light regulation). North Korea and Cuba are among the few remaining largely command economies. The UK, USA and most of Europe are mixed — markets allocate most resources, but the state provides healthcare, education and defence, and regulates heavily. The collapse of the centrally planned Soviet economy in 1991 is often cited as evidence of the difficulty of planning without price signals.

1.1 Recap — nail these

- Scarcity (finite resources, infinite wants) forces choice, and every choice has an opportunity cost. - Positive = testable fact; normative = value-judgement opinion (look for should/ought). - A PPF: on it = efficient, inside = inefficient, outside = unattainable; concave = increasing opportunity cost; outward shift = growth. - Division of labour raises productivity but risks boredom & interdependence; money makes specialisation possible. - Economic systems sit on a spectrum from free market → mixed → command.