1. Basic economic ideas and resource allocation

Scarcity is the fundamental economic problem: wants are unlimited relative to the finite resources available to satisfy them.

Because land, labour, capital, time and enterprise have alternative uses, choosing one use prevents some other use. Scarcity exists for individuals, firms and governments, even when a particular good is abundant.

A government with a fixed health budget cannot fund every hospital, treatment and prevention programme at once.

Scarcity does not mean a resource is rare or that everyone is poor; it means supply is limited relative to competing wants.

Economic choice is the decision about which scarce resource use to pursue. Every choice selects one option and leaves at least one alternative less funded or forgone.

Individuals choose consumption or saving, firms choose products and methods, and governments choose public priorities. The best decision depends on objectives, constraints and expected consequences.

A firm can use a factory line for bicycles or electric scooters; producing more of one leaves less capacity for the other.

Choice is not limited to buying goods: deciding not to act, to save or to regulate is also an allocation decision.

Opportunity cost is the value of the next-best alternative given up when a choice is made. It is forward-looking and depends on the alternatives actually available.

The chosen option is not itself the opportunity cost. Identify the best rejected use of the same scarce resource, then compare its benefit with the chosen use.

If a student spends Saturday revising instead of working a paid shift, the opportunity cost is the wages from the best available shift, not the revision itself.

Opportunity cost is not always a cash payment and is not the sum of every rejected option.

Resource allocation is the process of deciding which goods and services are produced, which production methods use scarce inputs, and who receives the resulting output.

A market may coordinate choices through prices and incentives; governments may allocate through rules, taxes, public provision or planning. Each method involves trade-offs and distributional consequences.

A city deciding between more buses and more roads is answering what to produce and how to use land, labour and capital; fares and access determine for whom the service is available.

Efficiency and fairness are different allocation questions: an allocation can maximise output while leaving access unequal.

Economics is a social science that studies how people and organisations make choices under scarcity and how those choices affect resource allocation and welfare.

It uses models, data and empirical evidence to explain behaviour, but human decisions are influenced by institutions, expectations, culture and policy, so predictions are conditional rather than laws of nature.

A model of how a tax changes demand can be tested against observed data, then revised if consumers respond differently from the assumptions.

Calling economics a social science does not make it opinion-only; it uses evidence, while recognising that behaviour and context matter.

A positive statement can be tested against evidence about what is or was. A normative statement says what ought to be and depends partly on values or priorities.

Policy arguments often combine both: a factual prediction may be positive, while the decision about whether the outcome is desirable is normative.

“A higher carbon tax reduces fuel demand” is testable; “the government should raise the carbon tax” adds a value judgement about climate benefits and distribution.

A statement is not normative merely because it concerns policy, and a positive claim can still be uncertain or disputed.

Ceteris paribus means “other things being equal”: analyse the effect of one change while treating other relevant variables as unchanged.

It isolates a relationship in a model, such as how a price change affects quantity demanded. In the real world, several factors may change at once, so the condition must be stated when applying the result.

“A rise in price reduces quantity demanded, ceteris paribus” holds income, tastes, prices of related goods and expectations constant.

Ceteris paribus does not claim other variables never change; it identifies the controlled comparison used to reason about one effect.

The short run is a period when at least one factor is fixed; in the long run all factors can be varied; the very long run also allows technology, institutions and population to change.

These are economic descriptions, not universal clock times. The relevant period depends on the decision and how fast inputs or capacity can adjust.

A restaurant may add staff in the short run but need the long run to expand its kitchen; over the very long run, cooking technology and consumer habits may change too.

Long run does not simply mean “a year” and does not guarantee that every adjustment is costless.

Land means natural resources; labour is human effort; capital is produced equipment and infrastructure used to make goods; enterprise organises resources and bears risk.

Capital is not the same as money: a machine is physical capital, while finance purchases it. Factors can be combined in different proportions and may be complements or substitutes.

A bakery uses land and energy, labour from bakers, ovens as capital and an entrepreneur who coordinates production and accepts uncertainty.

Entrepreneurship is not merely owning a business, and “capital” in economics does not mean every financial asset.

Human capital is the education, training, health and experience embodied in people. Physical capital is manufactured equipment, buildings and infrastructure used in production.

Both can raise productivity, but they differ in ownership, depreciation and how they are expanded. Human-capital investment changes people’s capabilities; physical-capital investment adds productive assets.

A firm’s training programme builds human capital, while a new automated machine is physical capital. Either may increase output per worker.

A worker is labour; the worker’s accumulated skills are human capital. A company’s cash balance is not physical capital.

The reward to land is rent; the reward to labour is wages; the reward to capital is interest; the reward to enterprise is profit.

These labels describe income flows to factors, but real-world incomes can combine roles—for example, an owner-manager may receive both wages and profit. Scarcity and productivity influence reward levels.

A landlord receives rent, employees receive wages, a lender receives interest and an entrepreneur keeps profit after costs.

Profit is not simply sales revenue: it is the residual after paying other costs and may be negative.

Division of labour splits production into specialised tasks; specialisation concentrates a worker, firm or country on a narrower activity in which it has an advantage.

Repetition and learning can raise productivity, and exchange lets specialists access other goods. The trade-off is dependence on coordination, demand and reliable supply, plus possible boredom or loss of flexibility.

An assembly line may let each worker master one stage and produce more phones per hour, but a missing component or disrupted supplier can stop the whole line.

Specialisation is not automatically beneficial: its gains depend on scale, transport, markets and the ability to trade.

An entrepreneur combines land, labour and capital, makes decisions and bears the uncertainty of whether the business will succeed. Profit is the potential reward for this role.

Entrepreneurship includes identifying an opportunity, coordinating production, innovating and responding to risk. The entrepreneur may also supply labour or capital, but the functions are distinct.

A founder hires staff, leases equipment and chooses a product before knowing whether customers will buy it; the residual profit or loss reflects that uncertainty.

Risk can sometimes be insured, but uncertainty about outcomes and entrepreneurial judgement are not the same as simply owning money.

A market economy relies mainly on private decisions and price signals; a planned economy relies mainly on state direction; a mixed economy combines markets with government intervention.

The distinction concerns how decisions are coordinated, not whether any government or private activity exists. Real economies lie along a spectrum.

A market may allocate housing through prices, a plan may set output targets and administered prices, while a mixed system allows private housing but regulates rents or supplies public housing.

“Mixed” does not mean half market and half plan; the balance and sectors involved matter.

In a market system, prices and profit signals guide resources; in a planned system, authorities set priorities and allocate inputs; in a mixed system, markets are modified by taxes, rules and public provision.

Each method can address some coordination problem while creating trade-offs: markets may respond quickly but leave externalities, while planning can target social goals but may lack information or incentives.

A government subsidy can redirect private investment toward renewable power without replacing the entire market allocation process.

No allocation system eliminates scarcity; it changes who decides and which signals or objectives are used.

A production possibility curve (PPC) shows the maximum attainable combinations of two goods or services from given resources, technology and institutions when resources are fully and efficiently used.

Points on the curve are productively efficient; points inside show underused or misallocated resources; points outside are unattainable with the current constraints.

A country choosing between food and machinery can move along its PPC by reallocating inputs, giving up some of one output to produce more of the other.

A point inside the curve is not impossible—it may be attainable but inefficient.

Moving along a PPC shows the opportunity cost of producing more of one output. A straight line implies constant opportunity cost; a bowed-out curve implies increasing opportunity cost as resources become less suitable for the new use.

The slope is the amount of the vertical-axis output forgone per extra unit of the horizontal-axis output, with sign depending on the graph convention.

If each extra machine costs two units of food, the PPC is linear. If increasingly specialised farmland is moved into machinery, food forgone per machine rises and the curve bows outward.

The curve’s shape is not an artistic choice: it encodes the transferability and opportunity cost of resources.

An outward PPC shift represents greater productive capacity; an inward shift represents reduced capacity. The cause may be a change in resources, labour skills, technology, infrastructure or institutional conditions.

A change affecting only one good can pivot or rotate the curve, while a broad improvement or shock can shift both intercepts. The curve does not move merely because the economy chooses a different point on it.

A new irrigation technology may increase the maximum food output and pivot the PPC outward toward food; a flood that destroys factories shifts machinery capacity inward.

Moving along a curve is reallocation; shifting the curve is a change in productive potential.

A point on a PPC represents productive efficiency: the available resources and technology are used to produce a maximum attainable combination. A point inside is attainable but inefficient; a point outside is currently unattainable.

The interpretation assumes the PPC’s resources, technology and institutional setting are fixed. An economy can move from inside towards the frontier by reducing unemployment or misallocation.

A country producing below its frontier may increase both food and machinery without a trade-off until it reaches the curve; moving along the curve then requires giving up one output.

A point outside is not “inefficient”—it cannot be produced with the current constraints.

A free good is available in enough quantity that no opportunity cost is normally required to use it. A private (economic) good is scarce, has an opportunity cost and can usually be made excludable through ownership or price.

The classification depends on context and technology. Air may be free in one setting but scarce and priced when cleaned or supplied in a cylinder.

A loaf of bread is a private good: using it leaves less for someone else and a seller can restrict access. Sunlight in an open field is usually treated as a free good.

“Free” means no opportunity cost, not merely zero money price; a free-to-user service may still use scarce resources.

A public good is non-rival: one person’s use does not substantially reduce another’s, and non-excludable: it is difficult to prevent non-payers from benefiting.

These properties create a free-rider problem, because individuals can wait for others to pay. Governments or collective arrangements may therefore provide the good, though congestion can make rivalry change at the margin.

A lighthouse signal can guide many ships at once and is difficult to withhold from a non-paying ship; national defence has similar properties.

Public does not mean government-produced and free does not mean no resource cost; the classification concerns rivalry and exclusion.

A merit good creates benefits that consumers may undervalue, so imperfect information can lead to under-consumption relative to the socially desirable level.

The market outcome reflects perceived private benefit, while education or vaccination may also create wider benefits. Policy can improve information, subsidise use or provide the good directly.

People may delay preventive health checks because they underestimate future benefits; reminders, information and subsidised access can increase uptake.

Calling a good merit does not mean every person must consume more; the economic issue is systematic information and welfare divergence.

A demerit good is consumed above the socially desirable level when consumers underestimate its harmful effects, often because information is imperfect or addictive behaviour distorts choice.

The market quantity reflects perceived private benefit and cost; education, regulation, taxation or age restrictions may reduce the gap, with trade-offs for liberty and enforcement.

A consumer may underestimate the long-run health cost of cigarettes, so an information campaign and excise tax can reduce consumption, though neither guarantees the socially optimal quantity.

A demerit good is not defined by being illegal or disliked; the key is systematic over-consumption relative to welfare.