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LR

Necessary Assumption

Overview

Necessary assumption questions ask for something the argument must assume to be true. Without this assumption, the argument falls apart. Use the Assumption Negation Test.

1.Use the Assumption Negation Test: negate each answer — if the argument falls apart, it's necessary
2.The correct answer is often more modest than you expect
3.Watch for scope shifts between evidence and conclusion
4.Necessary assumptions bridge unstated gaps — they don't prove the conclusion
This new drug reduces cholesterol. Therefore, it will reduce heart disease.

The argument assumes which of the following?

Answer A: The argument assumes cholesterol is linked to heart disease. Negate it: "cholesterol has no connection to heart disease" — the argument collapses. That's the necessary assumption.
✗Choosing answers that are too strong (sufficient, not necessary)
✗Failing to use the negation test
✗Selecting answers the argument states rather than assumes
← Sufficient Assumption
Flaw Questions →
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