Economics as a social science — Edexcel A-Level Economics A
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Economics as a social science explained
Ceteris paribus means 'all other things being equal'.
Read the full explanation
Economists use it when isolating the effect of one variable on another: to say that a rise in price reduces quantity demanded ceteris paribus is to hold incomes, tastes, prices of substitutes and other influences constant. In model building, ceteris paribus allows a single cause-and-effect relationship to be stated and tested, and it underpins curves such as demand and supply. Without it, several variables could change at once and no clear link could be identified. In assessment, you should recognise ceteris paribus as a simplifying device, apply it to a stated change, and explain that in the real world other factors may also move, so predictions are conditional.
Your focus
- Define ceteris paribus accurately.
- Explain how ceteris paribus is used to isolate a single relationship in a model.
- Apply ceteris paribus to a stated economic change and identify the factors held constant.
Economics as a social science exam tips
Marking Points
- Ceteris paribus means holding all other relevant factors constant while one variable changes.
- It is used to isolate the effect of a single variable, such as price on quantity demanded.
- It underpins the construction of economic curves and relationships used in models.
- Predictions made under ceteris paribus are conditional because in reality several variables may change together.
- Applying it correctly means naming the variable changed and the factors held constant.
Examiner Tips
- 💡Identify the option that correctly pairs one changing variable with others held constant.
- 💡Reject options implying that ceteris paribus makes a prediction unconditional or guaranteed.
- 💡Use the phrase 'all other things being equal' to check whether an option matches the definition.
Common Mistakes
- Thinking ceteris paribus means nothing else ever changes; the correction is that it is an assumption used for analysis, not a description of reality.
- Applying it without naming which factors are held constant; the correction is to state the variable changed and the influences kept fixed.
- Treating a ceteris paribus prediction as certain; the correction is that it holds only if the other factors really stay unchanged.
- Confusing ceteris paribus with the fallacy of composition; the correction is that ceteris paribus concerns holding other variables constant, not generalising from one part to the whole.