#14 - Some freelance journalists sell their work to magazines that have lax

[Administrator]

Complete Question Explanation

Parallel Flaw. The correct answer choice is (C).

The stimulus relies on Formal Logic. In Parallel Reasoning and Parallel Flaw questions, when the stimulus relies on Formal Logic and/or Conditional Reasoning, it is very frequently helpful to represent the relationships in the premises and conclusion diagrammatically. Then, each answer can be diagrammed, and a match more easily identified. While this can take time, if you master the process of diagramming, it need not take too much time to do under testing conditions. And the certainty the diagramming process yields is well worth it. Below is a diagrammatic representation of the Premises and Conclusion of the stimulus, using these abbreviations:

FJ = freelance journalist
SLM = sell to lax magazines (i.e. sell to magazines with lax editorial standards)
SRW = self-respecting writer

Premises: FJ SLM SRW

Conclusion: SRW FJ

Notice that while the premises DO give us a basis for saying that some freelance journalists are not self-respecting writers, in Formal Logic we are not permitted to infer the "contrapositive" of statements with a "Some Arrow." Thus, when the conclusion attempts to preserve the Some Arrow but negate the components of it, it is attempting this kind of illicit contrapositive and is flawed. We need to find the same flaw.

Answer choice (A):

Premises: HST TB KT
Conclusion: T ---not all----> TB

The conclusion in answer choice A is valid, moreover the diagrammatic structure does not match, so answer choice A is incorrect.

Answer choice (B):

Premises: SBM T PAT
Conclusion: SBM ---few---> PAT

Answer choice B is flawed, though for a different reason than the stimulus, as the diagramming structure clearly shows. Answer choice B is flawed, because although we can conclude that most school board members do not prefer administrative work to teaching, this still allows that there could be many school board members (as many as 49%) who do prefer administrative work to teaching.

Answer choice (C): This is the correct answer choice.

Premises: S PHM MCC
Conclusion: MCC S

The diagrammatic structure matches, and the flaw is the same: while we have the basis to conclude that some students are not members of the Calculus Club, we cannot negate those terms and put the Some Arrow between them ("some" statements do not imply their "contrapositive").

Answer choice (D):

Premises: P HD ADT
Conclusion: P ADT

Answer choice D is valid reasoning, following the inference chain that the premises allow us to make. Thus, it is incorrect.

Answer choice (E):

Premise: LSE P
Premise: C LSL3
Conclusion: P C

The premises do not connect, because there are no definitely common terms (we cannot assume coaches are teachers; and we cannot assume not letting students leave before 3 is the same as not letting students leave early). Thus, the conclusion is flawed, but for a different reason than the stimulus, as the diagramming shows. Answer choice E is therefore incorrect.

[Robot1212]

FJ sell to mag with lax standards
Self respecting writer -> /lax standards
Conclusion: Self respecting writer -> /FJ

simplified:
A B
C -> /B
Conclusion: C -> /A

The flaw is that you cant take the contrapositive of a some statement. So you cant say /B /A .
Thus, All we know is A B -> /C or back to the example..

A) HT B
KT -> /B
Conclusion: Some Teachers dont teach Bio

This is actually a valid argument

B) SBM T
T -> /prefer admin over teaching

Conclusion:
Few = some and /most
SBM prefer admin over teaching
SMB /prefer admin over teaching

seems valid to me


C)
Premise: S history > Math
Premise: CC -> / history>Math
Conclusion: CC /CC

bingo. see simplified version and matches step for step



D) P HD
AD -> / HD
Conclusion: P /AD

seems pretty valid to me

E)
Leave early Popular
Coach -> /leave before 3
conclusion: Pop /C

Yea. This is flawed for multiple reasons but here is the simplified version. Even if we assume that /leave before 3 is equal to /leave early, the argument still doesnt connect to make the conclusion true.

[ealanclos]

Hello,

I got this one correct, but for some reason I'm having a hard time pinpointing the flaw. I diagramed the question stimulus like this:

FJ (freelance journalists) -> Magazines with lax standards
Self-respecting writer -> /magazines with lax standards
Conclusion: self-respecting writers ->/FJ

I can tell that this is flawed but can't quite articulate the problem. I appreciate the help!

[Adam Tyson]

The flaw in this stimulus is based on Formal Logic, ealanclos, and that is triggered by the crucial use of the word "some." The stimulus tells us that SOME freelance journalists do this thing that self-respecting writers never do. We could use that to conclude that SOME freelance journalists are not self-respecting writers. The flaw is in reversing that inference, like creating a contrapositive in a conditional relationship, saying that some self-respecting writers are not freelance journalists. In Formal Logic, you can't do that! The reason is that it could be true that every self-respecting writer is a freelance journalist, even while there are some additional freelancers who are not self-respecting.

If you are a Powerscore course or tutoring student, you can find more info about Formal Logic in the Online Student Center. There's also a chapter devoted to it in our LR Bible. It's similar to conditional reasoning, but there are some important differences well worth studying!