As we discussed in the previous lesson, there are two types of Assumptions seen on LSAT questions: Sufficient Assumptions and Necessary Assumptions. These questions will typically ask to identify and fix the arguments within. So, these can also be referred to as Strengthening/Weakening Questions.

CHALLENGE: Identify the Necessary Assumptions

Necessary Assumption questions have stems phrased in the following ways:

  • The argument requires/depends on/relies on the assumption that
  • Which of the following is an assumption on which the argument relies/depends?
  • Which one of the following is an assumption the argument requires?
  • The argument requires/depends on/relies on assuming which one of the following?

Notice that Necessary Assumption questions always contain a word that means necessary or required, while Sufficient Assumption questions ask for a guarantee that the conclusion will be reached.

Intro (0:01) | Ex.1 (4:23) | Ex.2 (13:09) | Trap Choices (18:07)
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Sufficient vs. Necessary Review

Next LSAT: September 21st

Sample Questions

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Next LSAT: September 21st