Blueprint LSAT Preparation: Logical Reasoning, Logic Games, and Reading Comprehension

These flashcards cover LSAT logical reasoning question types, argument structures, conditional logic fallacies, logical force, causal reasoning, specific task-based strategies, and foundational concepts for games and reading comprehension.

Soft Must Be True Question

A question type asking for the answer choice that is almost certainly true if the information provided in the passage is true.

Strengthen Question

A question type that requires identifying the answer choice that makes the passage's argument more convincing.

Soft Must Be True (Principle) Question

A question asking for the answer choice that presents a valid argument based on a specific rule provided in the passage.

Parallel (Principle) Question

A question asking for the answer choice that presents a valid argument using the same implicit rule as the passage.

Must Be False Question

A question requiring the identification of an answer choice that cannot be true if the passage's information is true.

Crux Question

A question that identifies information relevant to determining the level of conviction or validity of the argument.

Describe Question

A question type asking for a description of how the argument uses its evidence to reach a conclusion.

Role Question

A question type asking to identify the specific function (e.g., premise, conclusion, subsidiary conclusion) a part of the passage plays within the argument.

Logical Reasoning Families

The three categories of logical reasoning: Implication, Characterization, and Operation.

Implication Family

Questions where the statements in the stimulus are accepted as true, including Must Be True, Soft Must Be True, and Must Be False.

Operation Family

A family of questions where answer choices are accepted as true to test their effect on the stimulus.

Premise Indicator Words

Words such as since, because, for, as, after all, given that, and moreover.

Conclusion Indicator Words

Words such as therefore, thus, hence, so, as a result, clearly, consequently, and it follows.

Subsidiary or Intermediate Conclusion

A conclusion that is supported by a premise but also acts as support for another conclusion.

Assumption

An unstated claim that must be true for a conclusion to follow logically from the premises.

Valid Argument

An argument structure where the conclusion must be true if its premises are true.

Invalid Argument

An argument where the conclusion does not necessarily follow from the premises, necessitating hidden assumptions.

Sufficient Condition

A condition that guarantees another condition will be met.

Necessary Condition

A condition that must be true for another condition to be met.

Fallacy of the Converse

An error in logic assuming that a necessary condition is sufficient to guarantee a result, represented by assuming $A \rightarrow B$ implies $B \rightarrow A$.

Fallacy of the Inverse

An error in logic assuming that the absence of a sufficient condition guarantees the absence of a necessary condition, represented by assuming $A \rightarrow B$ implies $\neg A \rightarrow \neg B$.

Contrapositive

A valid logical inference stating that if a necessary condition is not met, the sufficient condition cannot be met: $\neg B \rightarrow \neg A$.

Weak Modality Keywords

Terms like may, might, can, could, possibly, and often.

Strong Modality Keywords

Terms like must, is, are, needs, will, does, do, and always.

Weak Quantification Keywords

Terms like some, few, several, a significant number, and many.

Strong Quantification Keywords

Terms like all, any, every, and nearly all.

Causal Conclusion Validity

On the LSAT, these are considered never valid because alternative causes are always possible.

Sufficient Assumption

An unstated claim that guarantees the argument is valid and the conclusion follow logically.

Necessary Assumption

An unstated claim that must be true for the argument to be valid; if negated, the argument becomes totally invalid.

Resolve Question

A question that requires an answer choice that resolves a paradox without invalidating either part of it.

Quantifier Quantity for 'Some'

Implies a quantity of 'at least one' (meaning it is not none).

Fallacy of Exclusivity

A flaw occurring when an argument fails to establish that options are exhaustive and exclusive before eliminating all but one.

Fallacy of Composition

The mistake of applying a characteristic of a whole to its parts, or vice versa.

Ad Hominem Fallacy

Attacking the individual proposing the argument rather than addressing the argument itself.

Absence of Evidence Fallacy

The mistake of claiming that the failure to prove a claim is evidence that the claim is false.

Principle of Distribution

A rule in logic games indicating that it is necessary to identify all possible distributions by working from extreme to equal.

Comparative Reading Comprehension Relationship

The essential link between two passages, which is always based on a shared topic, theme, or point of view.