Equality means everyone gets the same. Equity means everyone gets what is fair. Those are not the same claim, and one of them is a value judgement rather than an economic fact. Getting that distinction right — and separating income from wealth — is what turns a vague answer on inequality into a precise one.
📚 What you need to know
Equality means outcomes are the same for different people or groups. Equity means outcomes are fair — a normative idea people disagree about.
Income is a flow (wages, rent, interest and profit, earned per period). Wealth is a stock of assets owned at a point in time.
Wealth inequality is almost always larger than income inequality, because wealth accumulates over lifetimes and generations.
Main causes: differences in human capital, unequal opportunity, unequal asset ownership, discrimination, bargaining power, tax and benefit policy, globalisation and technology.
Costs of inequality: slower growth, worse living standards for the poorest, and reduced social and political stability.
Some inequality is defended as an incentive to work, study and take risks. Perfect equality would remove that incentive.
The question is never “should there be inequality?” but “how much, and of what kind?”
Equality is measurable. Equity is arguable.
If two workers in the same job are paid different amounts, that is inequality — an observable fact. Whether that difference is acceptable is a question about equity, and reasonable people answer it differently.
Most people accept that a surgeon should earn more than a shop assistant. The disagreement is about how much more, and whether the gap reflects genuine differences in skill and effort or just differences in luck, background and opportunity. Economics can measure the gap; it cannot settle the argument for you.
In an exam, always flag equity as a normative concept and inequality as a positive one. Examiners look for that word. It shows you know the difference between what is and what ought to be.
Income is a tap. Wealth is the water in the tank.
This is the metaphor to hold on to. Income arrives continuously and can be spent, taxed or saved. Whatever gets saved and invested piles up as wealth. Wealth then generates more income in the form of rent, dividends and interest — so the tank refills the tap.
Because wealth builds up over years and can be inherited, wealth is distributed far more unequally than income in nearly every country measured.
Why this matters for the exam. A policy that raises income tax touches the flow. A policy that taxes inheritance or property touches the stock. If a question asks about wealth inequality and you only discuss wages, you have answered a different question.
WORKED EXAMPLE
Classify each of the following as income inequality or wealth inequality, and justify. [4]
(a) The top 10% of households receive 28% of all annual earnings. (b) The top 10% of households own 45% of all property and shares. (c) A family inherits a debt-free house worth $400,000. (d) A graduate’s starting salary is double the minimum wage.
Test: is it “per year” or “owned”?(a) Income — earnings are a flow received over a period(b) Wealth — property and shares are assets held(c) Wealth — a one-off transfer of an asset, not a flow(d) Income — a salary is a flow(a) and (d) income; (b) and (c) wealthNotice the top 10% hold a much larger share of wealth (45%) than of income (28%). That gap is the normal pattern.
Why inequality builds on itself
Inequality is not a snapshot that resets each year. Advantage and disadvantage both compound, which is why gaps that start small can widen across a lifetime and across generations.
Neither household did anything differently on any single day. The gap widens because the same behaviour has opposite effects depending on where you start.
The causes of inequality
Cause
How it produces inequality
Differences in human capital
Higher skills and qualifications raise productivity, so employers pay more. A weak education system widens the spread of skills and therefore of pay.
Unequal opportunity
Access to good schooling and healthcare varies by region and by family income, so talent in poor households never gets developed.
Unequal asset ownership
Assets generate income. Households that already own property and shares receive an income stream that non-owners simply do not have.
Discrimination
Pay or hiring gaps by gender, ethnicity, age or disability push some groups’ incomes below what their productivity would justify.
Unequal bargaining power
Where union membership is low and jobs are insecure, workers cannot bargain for a share of productivity gains, so profits rise faster than wages.
Tax and benefit policy
A progressive tax system with generous transfers narrows the gap between market income and disposable income. A regressive one widens it.
Globalisation and technology
Both raise returns to high-skilled workers while exposing low-skilled workers to competition and automation, stretching the wage distribution.
What inequality costs an economy
Notice that these are economic arguments, not just moral ones. That is what makes them usable in an essay.
Slower growth. Poorer households cannot afford education or training, so human capital goes undeveloped and the economy’s productive potential is smaller than it could be.
Weaker aggregate demand. Low-income households spend a larger share of any extra income than rich ones. Concentrating income at the top can therefore reduce total consumption.
Higher government spending. More households need benefits, housing support and health services, while the tax base is narrower.
Worse living standards at the bottom. Relative poverty means exclusion from things society treats as normal, which harms health and children’s outcomes.
Social and political instability. Very unequal societies tend to see higher crime, lower trust and more political volatility — all of which deter investment.
But is some inequality necessary?
Do not write a one-sided answer. The standard defence of inequality is incentives:
Wage differentials reward the effort and cost of acquiring skills. If a doctor earned the same as everyone else, fewer people would spend seven years training.
Profit rewards risk-taking. Entrepreneurs accept the chance of losing everything because the upside is large.
Perfect equality removes the price signal that moves labour into the industries where it is most needed.
The counter-argument is that beyond some point the incentive effect is exhausted, and further inequality simply reflects inherited advantage rather than effort. Where that point lies is exactly the equity question — a value judgement, not a calculation.
WORKED EXAMPLE
Explain why wealth inequality is usually greater than income inequality. [4]
Point 1: wealth accumulates, income does not
Income is spent each year. Whatever is saved adds to a stock that carries over and keeps growing.
Point 2: saving is not proportional
Low-income households spend nearly all their income, so they save almost nothing. High-income households save a large share.
Point 3: wealth earns a returnAssets pay rent, interest and dividends, adding to income and then to wealth againPoint 4: it transfers between generations
Inheritance passes accumulated wealth on, so gaps persist across generations rather than resetting.
Compounding plus inheritance widens the stock more than the flowA good sentence to finish on: income inequality in one year becomes wealth inequality in the next decade.
💡 Exam tip
Define equity as normative and inequality as positive in the first two lines. It is a cheap, reliable mark.
State clearly whether you are discussing income or wealth, and use the words flow and stock.
Give causes as chains: poor education → low human capital → low productivity → low wages → low income.
Use economic costs, not only moral ones. Growth, aggregate demand and government finances are the ones that score.
Always include the incentive argument for some inequality — it is the standard counterweight in an evaluation.
If the question mentions a specific group or country, use it. Concrete beats general every time.
⚠ Common mix-up
Equality and equity. Equal treatment and fair treatment are different claims, and only one is measurable.
Income and wealth. A high earner with large debts may hold negative wealth; a retired person with a small pension may own a valuable house.
Inequality and poverty. A country can be very unequal with almost no absolute poverty, or fairly equal and mostly poor.
Assuming inequality is always rising. It depends on the country and the period, and on whether you measure before or after taxes and benefits.
Arguing only from morality. Examiners want the economic mechanism, not just the sentiment.
Ignoring the incentive case. A one-sided answer cannot reach the top evaluation band.
Up next: Measuring Inequality: the Lorenz Curve and Gini Index — how economists turn all of this into a single number you can compare across countries.
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