Q19 - Political scientist: All governments worthy

[case0403]

I am having a hard time with this type of question. Can someone please show me what the pattern is and how to find the flaw. I choose answer (E). Sure hope that wasn't an easy one to get rid of. HA

[cyruswhittaker]

This argument has a conditional structure, and its flaw is that it reverses the second conditional (second sentence) in order to arrive at its conclusion:

First Sentence:

GWR-->ACD

(GWR= governments worth of respect; ACD=Allow Citizens to Dissent)

Second Sentence:

GWR-->~(MU)

(MU=Minories unprotected)

So a governement worthy of respect does not leave minorities unprotected.

Conclusion:

~(MU)-->ACD

"Does not leave minorities unprotected" is equivalent to "protects minorities" and "allows citizens to dissent" is equivalent to "permits criticism of policies."

So the flaw is that the argument reversed the second statement (without negating both sides, which would have resulted in the logically equivalent contrapositive), and then combined it with the first sentence to form the conclusion.

Here's an abstract form:

A-->B
A-->C

Therefore, C-->B

So the fallacy was taking C-->A as a true statement.

The conditional reasoning in answer choice B is the exact match of this flaw.

I immediately crossed E out without even looking at the logical structure when I saw the word "should" as part of the conclusion.

[ManhattanPrepLSAT2]

Great explanation! Please chime in if anyone would like further discussion.

[mcmassier]

My concern is that the answer goes from talking about jazz musicians to talking about musicians in general. And the argument discusses governments in general throughout. How can the generalization in the answer match the generalization above it there is a term shift in one and not the other?

[deweykang]

My concern is that the answer goes from talking about jazz musicians to talking about musicians in general. And the argument discusses governments in general throughout. How can the generalization in the answer match the generalization above it there is a term shift in one and not the other?

That's interesting, I could definitely see that now that I'm looking at it again.

This is how I see it:

[governments worthy of respect] vs [jazz musicians]
*I guess you could take 'worthy of respect' part and overlay that with 'jazz'. (What kind of governments? Those that are worthy of respect. and What kind of musicians? Jazz musicians)

The 'worthy of respect' part is gone in the conclusion. It just mentions 'any government', which mirrors 'all musicians' in (B).

So to go refer back to what you were saying, the stimulus talks about 'governments worthy of respect' to 'any governments', and in (B), 'jazz musicians' to 'all musicians'.

(Correct me if I'm wrong, moderators! )

[etwcho]

Hey all, quick question.

Would the pattern of reasoning be correct if "any" in the beginning of the conclusion is substituted with "some"?

So it would look like.....this?
A --> B
A --> C

Some C --> B

Thanks in advance!

[ohthatpatrick]

Yeah, you're right.

That would turn into a simple quantity overlap inference.

For example, if I say:
All puppies are cute
and
All puppies are hairy
then it's fair to conclude that some hairy things are cute.

[technically, we need to know that at least one puppy exists, but LSAT, to my knowledge, has never been THAT obnoxious ... when you see a generalization like All A's are B's, it's implied that at least some A's exist]

To answer the previous poster's request for confirmation, you nailed it! The original argument contains not only the conditional logic flaw but also the scope shift from "governments worthy of respect" to "government", which (B) duplicates with a shift from "jazz musicians" to "musicians".

We end up not needing to see that to get the wrong answer, but it seems like the test writers might have thrown that in just to make (B) less appealing / more confusing.