I. Modify Arguments

Modify Arguments

Perhaps one of the most difficult parts of the Logical Reasoning part of the LSAT is modifying arguments. In ‘modifying arguments’ type of questions, you will be asked to strengthen or weaken arguments. You can do this by increasing or decreasing the validity of an assumption since assumptions are statements in arguments that are taken to be true.

Language cues for ‘modifying arguments’ questions

  • Most strengthens
  • Most supports
  • Most justify
  • “. . . strengthens . . . except . . .”

Solving ‘modify arguments’ questions

  • In answering questions that ask you to weaken arguments, find the necessary assumption in the passage because this is often what the correct answer will target.
  • Causal fallacies are commons in this type of questions. Sometimes you have to strengthen or weaken the causal connection between two ideas.
  • When answering questions that ask you to weaken an argument that compares two ideas, try to look for something that will undermine the comparison.
  • Avoid common traps like irrelevant answer choices or statements that require additional facts not present in the passage or question.
  • Keep an eye out for sweeping statements that use words like all, always, never, none, only, and etc. These statements are easier to refute because you need only one exception to disprove the argument.
  • On the other hand, qualifying statements use words like some, sometimes, usually, and probably. These statements make soft claims which make arguments harder to refute.

II. Statistical Reasoning

Statistical Reasoning

Statistical fallacies are another form of causal fallacies, and these fallacies are relatively common in the LSAT. This is why it is important to familiarize yourself with them so you can avoid committing these fallacies yourself.

  1. Biased Sample Fallacy

The biased sample fallacy is when you draw data from a statistical inference from a sample that is not representative of the population under consideration.

  1. The Texas Sharpshooter

The Texas sharpshooter fallacy is cherry-picking data cluster to suit the assumption you made. Instead of analyzing the data and forming a conclusion, you use your hypothesis to choose which parts of the data will support it.

  1. Insufficient Sample Fallacy

Also known as “hasty generalization,” this fallacy is when you draw a conclusion from an inadequate sample or premises.

  1. Correlation vs. Causation

Correlation refers to a statistical link between two things, while causation is when one thing causes another thing. It is common for test-takers to confuse these two concepts. Some things may be in correlation with each other but are taken as having causal relation.

  1. Confounding Factors

Also known as “lurking variables,” confounding factors are additional factors that may be responsible for a correlation.

  1. Improperly Weighing Cost-Benefit/Advantages

This error in thinking is when one incorrectly weighs the advantages and disadvantages of something. This is an error in one’s evaluation where the cost-benefit of something is not properly analyzed.

  1. Confusing Possibilities and Certainties

This error in thinking occurs when one thinks that just because something is a possibility then it is already a certainty, which is incorrect.

III. Weaken Reasoning

Weaken Reasoning

This type of question asks you to find statements that weaken or decrease the strength of an argument. An answer does not necessarily have to refute the argument completely. It only has to make it significantly weaker. The steps for solving this type of question is similar to the steps in solving ‘modify arguments’ questions.

IV. Paradox Questions

Paradox Questions

A paradox is a statement that is seemingly absurd or self-contradictory at first but may actually be true when investigated further. Paradox questions will ask you to resolve the given paradox or explain how the contradiction can reasonably exist.

Solving ‘paradox questions’

  1. Read the argument carefully and find the paradox or contradiction.
  2. State the paradox or contradiction in your own words.
  3. Use the process of elimination to find the answer choice that will best explain both sides of the paradox or contradiction.

V. Evaluate Questions

Evaluate Questions

In these questions, you will be asked to provide a premise that will strengthen an argument with faulty reasoning. You will have to explain how an argument could still be true. In other words, you have to present information or a statement that could either significantly strengthen or weaken an argument.

Solving ‘evaluate questions’

  1. Read the passage carefully and find the faulty statement or discrepancy in reasoning.
  2. State the fault or discrepancy in your own words.
  3. Eliminate the answer choices one by one to find the answer that best explains the fault or complete the discrepancy in reasoning.
  4. Avoid common trap choices such as choices that deny the idea which the question asks you to explain or statements that explain something not directly referring to the passage.

VI. Modify Questions

Modify Questions

One of the most common types of traps in ‘modify reasoning’ questions is when the answer choice shows the opposite of what the question stem presents.

Some common tricks used in the LSAT to catch unwary students are the following:

  • “All of the following may be inferred from the passage EXCEPT. . .” Then the question gives one answer choice that can be absolutely inferred from the passage.
  • The question asks for an assumption of an argument, then one of the answer choices is a summary of the argument.
  • The question asks which of the answer choices strengthens or weakens the argument, but one of the choices does the exact opposite of what is asked.

Trick Answer Type: Trick Opposites

This trap involves contradicting the question stem. This trap is very common on Strengthen/Weaken questions where the answer choice does the opposite of what the stem wants:

Here are examples of these deliberate tricks intended to catch students who rush through questions:

  • All of the following may be inferred from the passage EXCEPT:
    Then the LSAT gives one answer that absolutely may be inferred from the passage (which test-takers tend to pick automatically if they forget the “EXCEPT”).
  • The stem asks for an assumption in an argument, and one of the answer choices is a summary of the argument (but not an underlying assumption).
  • Which of the following weakens the argument above?
    Then the LSAT gives an answer choice that obviously strengthens the argument.

On test day, expect to run into a stem that looks like this:

All of the following are true, EXCEPT:

The translation of “EXCEPT” is that, of the five choices, all of them fit the condition EXCEPT one of them.

All of the following are reasons to go to business school EXCEPT:

(A) networking with future powerful executives
(B) eager to learn accounting
(C) increase your income
(D) impress your friends
(E) hone your poetry skills

Next LSAT: June 3rd

Review Questions

These are simulated LSAT questions and are under development. Question revisions will be completed by January 2020.


Total questions: 9

Quiz Length: 14 Minutes


Total questions: 6

Quiz Length: 9 Minutes

Next LSAT: June 3rd

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