LSAT glossary: 59 terms defined in plain English
The LSAT has its own vocabulary: sufficient assumption, scope shift, contrapositive. This glossary defines 59 of those terms in plain English, each with a small example. No jargon about jargon.
Logic core
- Assumption
- Conclusion
- Conditional Chain
- Conditional Statement
- Contrapositive
- Counterexample
- Deductive Reasoning
- Formal Logic
- If and Only If
- Inductive Reasoning
- Intermediate Conclusion
- Necessary Assumption
- Necessary vs. Sufficient Conditions
- Only If
- Premise
- Some and Most Statements
- Sound Argument
- Sufficient Assumption
- Unless
- Valid Argument
Question types
- EXCEPT Questions
- Flaw in the Reasoning
- Inference
- Main Point
- Method of Reasoning
- Parallel Reasoning
- Point at Issue
- Principle
- Resolve the Paradox
- Role of a Statement
- Strengthen
- Weaken
Common flaws
- Ad Hominem
- Appeal to Authority
- Appeal to Ignorance
- Circular Reasoning
- Correlation vs. Causation
- Equivocation
- False Dilemma
- Hasty Generalization
- Part to Whole
- Percentages vs. Numbers
- Scope Shift
- Slippery Slope
- Straw Man
- Whole to Part
Reading Comprehension
- Author’s Attitude
- Comparative Reading
- Main Idea
- Paragraph Function
- Passage Organization
- Primary Purpose
Test and study terms
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Last updated October 12, 2026