LSAT 91 - Section 2 - Question 14

This is a Parallel Flaw Method of Reasoning question.

The question tests your understanding of quantifier and conditional logic.

The argument in the stimulus translates to:

fl-journalist ←s→ sell-lax-mag → /self-respecting

__________________

/fl-journalist ←s→ self-respecting

The conclusion is flawed. The valid conclusion that could have been drawn is:

fl-journalist ←s→ /self-respecting

Generalizing from this particular flawed argument, the form is this:

A ←s→ B → /C

__________________

/A ←s→ C

We need to find the same form in one of the answer choices.

Answer Choice (A)’s premise translates to:

high-school ←s→ bio → /kindergarten

In order for (A) to be right, the conclusion should have said:

/high-school ←s→ kindergarten

Or in English, “Some kindergarten teachers are not high school teachers.” But it doesn’t say that. It says “Biology is not taught by all teachers.” That’s a valid conclusion. It follows simply from the premise that kindergarten teachers don’t teach biology.

Answer Choice (B)’s premise translates to:

sbm —m→ teacher → /prefer

Like (A), this is a good setup for (B) to be right. In order for (B) to be right, the conclusion should have said:

/sbm ←s→ prefer

Or in English, “Some non-school board members prefer admin work to teaching.” But it doesn’t say that. It says, “Few school board members prefer admin work to teaching.”

Correct Answer Choice (C)’s premise translates to:

student ←s→ prefer → /member

In order for (C) to be right, the conclusion needs to say:

/student ←s→ member

Or in English, “Some members of the Calculus Club are not students.” That’s exactly what the conclusion in (C) says. This is an invalid conclusion. The valid conclusion is “student ←s→ /member” or “Some students are not members of the Calculus Club.”

Answer Choice (D)’s premise translates to:

princ ←s→ harsh-disc → /adviser

In order for (D) to be right, the conclusion should have said:

/princ ←s→ adviser

Or in English, “Some advisers to a debate team are not principals.” But it doesn’t say that. It says, “Some principals are not advisers to a debate team.” That’s a valid conclusion.

Answer Choice (E)’s premise translates to:

popular ←s→ leave-early

coaches → /leave-before-3

(E) is already wrong for the fact that the premises do not connect.

As a Blind Review exercise, we can fix (E) up:

popular ←s→ leave-early → /coach

Fixing the premises like this gives (E) a chance. (E) could say that, therefore, some coaches are not popular teachers. That would be the same formal flaw in the stimulus and therefore make (E) the right answer.