#21 - The mayor was not telling the truth when he said that

[Administrator]

Complete Question Explanation

Flaw in the Reasoning. The correct answer choice is (A)

This stimulus begins with a short sentence that does have some potential to confuse, in part because
of the use of a double negative. The author says that the mayor was not being honest when stating
that the renovation of a bridge was not a waste of money. In other words, in the eyes of the author,
the bridge renovation was a waste of money, and the mayor was lying about it.

The author’s assertion is based on the fact that the bridge renovation was part of the Southern Tier
Project, which a government commission declared horribly wasteful. The argument can be broken
down as follows:

• Premise: The bridge renovation was part of the Southern Tier Project
  
  Premise: The Southern Tier Project was deemed egregiously wasteful by a government
  commission on waste.
  
  Conclusion: Therefore the bridge renovation must have been wasteful, and the mayor’s
  claims to the contrary must be lies.

When the argument is deconstructed, its flaw becomes a bit clearer: Just because the Southern
Tier Project was found to be wasteful overall, this does not mean that everything done within
the Southern Tier Project was wasteful. This is a classic error of composition and division—the
assumption that something known to be true of a whole must also be true of its component parts.

The question that follows is a Flaw question, so the correct answer choice will describe the error of
composition and division that is reflected in the author’s reasoning.

Answer choice (A): This is the correct answer choice. The author believes that every project that
is part of the Southern Tier Project must be wasteful, based solely on the fact that the Southern Tier
Project is wasteful overall.

Answer choice (B): Many test takers found this answer appealing, but this choice, in a sense, has
things reversed; the author does not draw a general conclusion based on a single instance—rather,
the author draws a conclusion about a component part based on the whole.

Answer choice (C): This choice describes a source attack—a personal attack on the source of the
argument rather than on its merits. This is not the problem with the author’s argument; the attack is
not personal, it is based on flawed reasoning.

Answer choice (D): This answer describes an argument that is largely circular—one in which the
conclusion is considered mostly true from the outset. This is not the issue with the argumentation
in the stimulus—the author does not presume the conclusion to be true, but instead supports it with
flawed reasoning—an error of composition and division.

Answer choice (E): This choice describes a flawed argument that is based on questioning the
motivations of the argument’s source. The author does accuse the mayor of lying, but does not
question the mayor’s motivations, so this choice can be ruled out of contention.

[LateBloomer]

Do you mind elaborating one why this is not a generalization beyond the reasoning of its not right because A is right?

[Adam Tyson]

Which answer did you want us to elaborate on, LateBloomer? I agree with all the descriptions in the official explanation of why the other answers were incorrect, so I am not sure what I could add there. The flaw is a whole-to-part flaw, aka an Error of Division. The Southern Tier Project may have been wasteful (assuming the report is accurate), but that does not prove that a particular portion of the project (the bridge) was also wasteful. Maybe the bridge was a good use of money and it came in under budget, but a road or other portion of the project was not needed and/or went over budget or was otherwise wasteful?

Let us know more specifically what concerns you have, either about the stimulus, the question, the correct answer, or one or more of the incorrect answers, and we will do our best to help clarify our thinking for you.

Thanks!

[Aysha.kh]

I did not understand understand how A is correct?

[Paul Marsh]

Hi Aysha! The explanation in the original post above does a pretty good job breaking down the argument, but I'll go through it again. If it still doesn't make sense, please follow up with a more specific question and one of us will help you.

This is a Flaw question. That means there is an error in the argument provided by the stimulus (to be more specific, there is an error in how the conclusion is drawn out of the premises.) The first step in any Flaw question is to identify the conclusion. Here that's: "The mayor was not telling the truth when he said that the bridge renovation did not waste taxpayers' money." Next, we identify the premises. There are two premises here, so our argument essentially looks like this:

Premise 1: The commission reported that the Southern Tier Project was wasteful.
Premise 2: The bridge renovation was part of the Southern Tier Project.
Conclusion: The bridge renovation did waste the taxpayers' money.

Does that conclusion follow perfectly and logically from our premises? Or is there an error there in how the conclusion is drawn? There are a number of errors that pop up again and again in these arguments - the PowerScore Bibles and Lesson Plan books do a great job of addressing a lot of these in their discussion on common Flaws (I'd highly recommend going through those sections if you haven't). One error that those books talk about is Errors of Composition and Division. Here's a link to a section of PowerScore's website that discusses that type of Flaw: https://www.powerscore.com/lsat/help/lr ... ion-errors

The example in that link is helpful: “The United States is the wealthiest nation in the world. So every American is wealthy.” This is obviously flawed reasoning - I don't know about you, but as an American public interest law student I sure don't feel particularly wealthy at the moment! Taking the characteristic of a whole or of a group and applying it to every member of that whole or group is a classic Flaw on the LSAT. When a premise is discussing a characteristic of a whole (e.g. "America is wealthy"), and then the conclusion automatically applies that characteristic to a part of that whole (such as "therefore this particular American must be wealthy"), that's a Flaw! And that's exactly what our argument in this question is doing.

As an aside, another Flaw in this argument is that the report of the commission is accepted by the argument as fact. But the Error of Composition/Division is such a major Flaw that pretty much whenever you spot it, you can be pretty sure that your correct answer choice is going to discuss it in some way.

Hope that helps! Again, if you have a more specific question about what's giving you a hard time with this problem, please follow up.