LSAT Logical Reasoning: 5 Tips for Inferences

In LSAT inference, the word “could” is a conditional (like “may” or “might”) and this type of vague qualifying language can drive even the most ardent LSAT student crazy. To do better on your LSAT test prep, and ultimately succeed on LSAT Test Day, you’ll need to get a handle on these tough Logical Reasoning LSAT questions. To recognize them on Test Day, look for those qualifiers. Examples: “Which of the following could be true based on the given argument?” “Which of the following conclusions could be drawn if the statements above are true?”


Test Breakdown

Inference questions count for just over 13% of the Logical Reasoning section, around 6 to 7 questions per test. There will also be 1 to 2 Principle questions per test that require an inference to be made.


 
By asking for an answer that must be true based on the statements in the stimulus, the LSAT is asking you to make a valid deduction from those statements. A deduction, as defined on the LSAT, applies logic more rigorously than most real-life deductions.
Here is an example of a real-life deduction. Suppose a house guest told you, “I don’t eat ice cream.” Given this fact about your guest, you might speculate, “She must be on a diet,” or “I wonder if she’s lactose intolerant.” Either is possible. However, neither of your reasonable speculations would be a valid deduction on the LSAT because neither must be true and neither follows unequivocally from the statement itself.
On the LSAT, a valid inference, were it negated, would contradict the given information. So, if the LSAT asked you for an inference based on your guest’s statement, the correct answer would be something like “If the only dessert I serve after dinner tonight is ice cream, she won’t eat any dessert.” This fact is conditional, a little convoluted, and may even seem obvious, but it must be true given that your guest does not eat ice cream.

5 Tips for Inference Questions


  • Reassess the question

    The nature of the question implies that there are only a finite number of statements that could be true “BASED” on the argument or statements. Inference questions are NEVER a matter of opinion. The word “could” implies a possibility, so the correct answer is really the strongest supported option.

  • Don’t be fooled by “half-right” answers

    There may be more than one choice that seems to relate to the argument or statements, or even seems to be somewhat supported by the passage, but only one choice will be the most supported or most logical. Don’t “fall in love” with a “half-right” answer choice early on.

  • Examine the scope

    What is the focus on the argument or statements? Something that “could” also be true will need to exist in the same rhetorical “world” as the initial passage. That doesn’t mean they have to share the same syntax, but they do need to share the same scope.

  • Eliminate extreme language

    “Could” is a qualifier, so answer choices with words like “none,” “never,” “always,” etc. should raise a red flag. They aren’t automatically incorrect, but make sure the tone of the answer choice fits the tone of the paragraph.

  • Ignore the assumptions

    This type of question is not about the argument’s structure and flaws, so you don’t need to focus on the underlying assumptions as much as you would for other questions. Rather, focus on understanding the basic premise and the conclusions that could be drawn from it. Remember: inferences are based on implications. Dig for those implications on your first-read!


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