Lsat Logical Reasoning

10 critical LSAT logical reasoning question types and strategies

What You'll Learn

Master LSAT logical reasoning question types with 10 flashcards covering strengthen, weaken, flaw, necessary assumptions, sufficient assumptions, and the negation test. Essential for law school prep.

Key Topics

  • Strengthen and weaken question strategies
  • Necessary vs. sufficient assumptions explained
  • Negation test technique for assumption questions
  • Common reasoning flaws: circular reasoning and causal reasoning errors

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How to study this deck

Start with a quick skim of the questions, then launch study mode to flip cards until you can answer each prompt without hesitation. Revisit tricky cards using shuffle or reverse order, and schedule a follow-up review within 48 hours to reinforce retention.

Preview: Lsat Logical Reasoning

Question

What is the main goal of a Logical Reasoning question?

Answer

To test your ability to analyze, evaluate, and complete arguments. Focus on identifying the conclusion, premises, and assumptions in short arguments.

Question

What is a conclusion in a logical argument?

Answer

The main point the author is trying to prove. Look for indicator words like 'thus,' 'therefore,' or 'hence.'

Question

How do you identify the premise of an argument?

Answer

Premises support the conclusion. Indicator words include 'because,' 'since,' and 'given that.'

Question

What is an assumption question?

Answer

It asks for something that must be true for the argument to hold. Strategy: Use the 'Negation Test' — if the assumption is false, the argument collapses.

Question

How do you approach Strengthen questions?

Answer

Find the answer choice that most supports the conclusion. Look for evidence that fills logical gaps or defends the argument from counterexamples.

Question

What do Weaken questions test?

Answer

Your ability to identify information that undermines an argument’s conclusion. Attack the link between premises and conclusion.

Question

What is a Flaw question?

Answer

It identifies logical errors. Common flaws: correlation vs. causation, circular reasoning, and generalization from small samples.

Question

How do you spot causal reasoning flaws?

Answer

Look for arguments assuming one event causes another. Ask if there could be another explanation or if correlation is mistaken for causation.

Question

What is a Parallel Reasoning question?

Answer

It asks for an argument with the same logical structure. Match type of reasoning, not topic.

Question

What is the best way to handle Inference questions?

Answer

Derive what must be true based on the given statements. Avoid adding outside information or making assumptions.

Question

What are 'Most Strongly Supported' questions?

Answer

They ask for the statement best supported by the passage. Use evidence directly from the text, even if not absolutely proven.

Question

What are Principle questions?

Answer

They involve applying a general rule (principle) to a specific case or identifying which principle the argument conforms to.

Question

How do you approach Disagree questions?

Answer

Find two speakers’ points of contention. Look for statements one agrees with and the other rejects.

Question

How do you deal with Logical Completeness questions?

Answer

Identify what would logically complete the argument, usually the conclusion or a missing premise.

Question

What is a 'Necessary vs. Sufficient' condition?

Answer

Necessary = required for the conclusion; Sufficient = guarantees the conclusion. Confusing the two is a common LSAT flaw.

Question

What’s a Conditional Statement?

Answer

An 'if–then' statement (If A → B). Remember the contrapositive (If not B → not A) is logically equivalent.

Question

How do you diagram conditional logic?

Answer

Write A → B for 'If A, then B.' Flip and negate for contrapositive: ¬B → ¬A.

Question

What’s the best way to time Logical Reasoning?

Answer

Average 1 minute 25 seconds per question. Don’t get stuck—flag and move on.

Question

Common mistake in LR?

Answer

Reading for content, not logic. Focus on reasoning structure, not subject matter.

Question

Tip for hard LR questions?

Answer

Predict the answer type before reading options; eliminate choices that don’t directly affect the argument’s logic.