LSAT Logical Reasoning Flaws in Politics

    LSAT Logical Reasoning | LSAT Prep

    If you're preparing for the LSAT, you are probably familiar with the sorts of flaws that commonly appear on the Logical Reasoning sections of the test. If not, there is an entire chapter devoted to Flaw in the Reasoning questions in the PowerScore LSAT Logical Reasoning Bible. You will almost certainly see such reasoning when you take the test, and political debating season provides countless examples as well...

    • “Look at that face. Would anyone vote for that?"     -Donald Trump

    In the quote above, Trump has made a Source Argument: This attack was clearly personal, directed at the candidate Carly Fiorina, rather than any particular argument Fiorina has advanced.

    This type of flawed argument, also referred to as an ad hominem attack, is directed at the person. or source of the argument, rather than at the arguments advanced. Proving himself a great exemplar of yet another type of flaw, the previously mentioned candidate attacked another candidate (rather than her policies) by saying “Look at that face,” and rhetorically asking “Would anyone vote for that?”, thus providing a great example of flawed argumentation.

    When you encounter this kind of reasoning on the test and are asked for the best description of the flaw, look for answer choices such as “The attack is directed against the person making the argument rather than directing it against the argument itself,” or “it draws conclusions about the validity of a position from evidence about a position’s source.”

    • There really are only two alternatives here. Either the issue of Iran obtaining a nuclear weapon is resolved diplomatically through a negotiation or it’s resolved through force, through war. Those are—those are the options.”          -Barak Obama               

    In this discussion of the options for dealing with Iran, Obama assumes that there exist only two courses of action, in spite of the fact that other options may be available. Coercive diplomacy, for example, provides something of a middle ground, in which diplomacy is continued, with additional signals of determination are made in an effort to pressure the other side into making concessions. This type of argument is commonly known as a False Dilemma. When you see similar logic on the LSAT and are responding to a Flaw question, look for the answer choice that provides a description such as “The author provides only two options from which to choose, without considering the possibility that a third option may also exist.”

    • "Not one of the 17 GOP candidates has discussed how they'd address the rising cost of college. Disappointing, but not surprising."     -Hillary Clinton

    The quote above exemplifies an instance in which Mrs. Clinton presented a General Lack of Evidence for the Conclusion. As it turns out, the problem of rising college costs is a major part of Marco Rubio’s platform, and Chris Cristie, Carly Fiorina, Rand Paul and Jeb Bush have all discussed the issue.  

    This describes the error made when an author or speaker attempts to prove a claim, yet provides no evidence that justifies the speaker’s conclusion. When you recognize such an error on the LSAT, and the stimulus is followed by a Flaw question, look for a description within the correct answer choice such as "the author draws a conclusion that is not warranted by the evidence provided," or "uses inapplicable information to draw a conclusion."

    • “I’d like to you take the camera off me and put it on the audience because I'd like to ask all of you, how many of you, raise your hand, believe that in today's Barak Obama America your children will have a better life than you've had."       -Chris Christie

    In the example above, Christie is Basing a Causal Conclusion on a Correlation. He is suggesting that the audience attribute to Obama any issues they might have with the current state of the country. Obama is the president, of course, and as such does have quite a bit of power, but certainly not enough to justify his taking blame for every one of the country’s problems.

    LSAT authors often make this error, providing evidence that two events are correlated, and concludes without justification that one must have caused the other. When you see this type of error in a logical reasoning stimulus, the right answer will provide a description such as "confusing the coincidence of two events with a causal relation between the two." or "assumes a causal relationship where only a correlation has been shown."

    • “…if you vote for Hillary, you are voting for the Ayatollah Khomeini to possess a nuclear weapon and if you elect me as president, under no circumstances will a theocratic ayatollah who chants death to America ever be allowed to acquire a nuclear weapon."     -Marco Rubio

    The quote above exemplifies a Straw Man argument, which describes the logically flawed strategy of distorting an opponent’s position in order to make it easier to attack or refute. Clinton would argue that with the recent Iran deal, she was actually looking to avoid nuclear war. When this error of reasoning appears on the LSAT, and the stimulus is accompanied by a Flaw question, look for the answer choice that provides a description such as "refutes a distorted view of an opposing position," or "mischaracterizes the opposing position, thus making it easier to challenge."


    It's valuable to recognize and understand these flaws, so that when you encounter them on the LSAT you can quickly identify them, and to be familiar with how such flaws are generally characterized in the correct answer choices. For more practice with Flaw in the Reasoning questions, as well as all other types of Logical Reasoning questions, pick up PowerScore’s QuestionType Training and Question Type Training II, and keep an eye out for further great examples of flawed reasoning in the upcoming debates!


    Preview the PowerScore LSAT Logic Games Bible

    Image: nine abstract arrows and one arrow in contrast, courtesy of Nate Bolt.