Unit 5
Weakening Arguments
About this unit
Read an argument and find the statement that most seriously undermines, contradicts, or exposes a flaw in its reasoning. You will learn to spot the hidden assumptions every argument makes — and find what would prove those assumptions wrong.
What types of questions will you face?
- 1A statistic or comparison is used to draw a conclusion — find what shows the comparison is unfair
- 2A cause-and-effect claim is made — identify the evidence that shows correlation, not causation
- 3A proposal or recommendation is given — find what would make it ineffective or counterproductive
- 4A generalisation is drawn — find the counterexample or hidden factor that undermines it
- 5A "success story" argument is made — identify what alternative explanation weakens the conclusion
Skills you will build
- Identifying the hidden assumption that an argument depends on
- Recognising when a sample is too small or unrepresentative
- Spotting alternative explanations for an observed outcome
- Understanding how context (e.g. population size) can make a statistic misleading
- Evaluating the relevance of each answer option to the specific argument made
By the end of this unit, you will be able to
- Identify the weakest point in any argument quickly and reliably
- Spot when a conclusion goes beyond what the evidence actually supports
- Recognise the classic logical pitfalls: cherry-picked data, false comparisons, unsupported generalisations
- Apply critical thinking to arguments across health, science, policy, and everyday life
Difficulty profile
Medium difficulty (avg 3.17). These questions are harder than Strengthening Arguments because you need to understand the argument deeply enough to find what would break it. Some involve subtle statistical traps.
Exam tip: Weakening Arguments
Ask: "What does this argument ASSUME to be true?" Then find the answer that shows that assumption is false or unreliable. The weakening answer doesn't have to disprove the conclusion — it just needs to cast serious doubt.
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