Q7 - Political advertisement: Sherwood campaigns as

[ManhattanPrepLSAT1]

The short answer to your question is no. The issue is that the conclusion says neither that rejecting Sherwood is sufficient to break the cycle of higher taxes, nor that it is necessary to break such a cycle. Instead the argument's conclusion is implicit: that Sherwood supports higher taxes. Why? Because Sherwood is on the city council which has supported higher taxes. Thus, answer choice (C) correctly describes the flaw in this argument.

However, if the argument was as you notated:

Sherwood --> Higher Taxes
----------------------------------------
~Sherwood --> ~Higher Taxes

In that case, negated logic would be expressed in the answer choices as "mistakes a sufficient condition for one that is necessary."

But since the argument does not contain conditional language cues, it's probably best not to try and force the statements into "if/then" relationships.

Incorrect Answers
(A) describes the wrong flaw. This argument doesn't generalize, rather it argues what is true of the whole is true of each member of the whole. This answer would have been even more tempting if the argument had argued from a part to whole, rather than whole to part.
(B) is contradicted. The argument clearly thinks that higher taxes is avoidable.
(C) describes the wrong flaw. There are no conditional relationships expressed in this argument.
(D) describes the wrong flaw. There is no ad hominem attack.

#officialexplanation

[ebbarnes]

Super quick question on #7. I took this PT 75 last night when I was very, very tired, and made an obvious mistake here. I understand now that this is a classic whole-to-part fallacy; I completely misread the stimulus where it indicates that the COUNCIL increased taxes. Sherwood opposes taxes, Sherwood is on the city council, the city council has consistently increased taxes, so we should reject Sherwood's bid for reelection to break the cycle of higher taxes. I totally get the flaw, and why E is the correct answer.

Here's my question. What if the stimulus did not say that the COUNCIL had increased taxes, but rather, that Sherwood HIMSELF had increased taxes? Then would C be correct?

The way I see it, the argument would then say:

If Sherwood --> higher taxes
If ~Sherwood --> ~higher taxes

Then, would this be an issue of mistaking sufficiency for necessity? Thanks so much!

[ganbayou]

About C,
Why we cannot think...
Increase →Sherwood
So it would be Sherwood→Increase, and reject him.

Why this is not the case?
At first C acutally seemed tempting

[kambizmashhadi]

great explanation but I still have difficulty differentiating between sampling flaw and part to whole flaw.
To me, it seems that an argument can sometimes have both flaws. Ex: all the cats are brown because my cat is brown.
this is a part to whole flaw , and it also can be interpreted as a sampling flaw.

Can you please differentiate these two flaws?

Thank you

[ohthatpatrick]

You're correct that Sampling and Part vs. Whole can overlap, but only in one direction:

If we're given evidence about a Part, and conclude something about the Whole,
we're assuming the Part is representative of the Whole. (we could call that 'sampling')

But you can't really spin that the other way around.

If we're given info about a Whole and conclude something about a Part,
it would be weird to use language like "we're assuming the Whole is representative of the Part."

'Sampling' implies extrapolation: moving from facts about a smaller subset of a population into a conclusion that speaks for a larger subset of the population.
e.g. "Most of the 3rd graders in my class could do long division. Thus, most 3rd graders can do long division."

LSAT wouldn't make us pick between Sampling and Part v. Whole when both are applicable.

(A) is saying that the author "based __X__ upon __Y__."

We base our conclusion upon evidence.

So it's calling the conclusion "the generalization"
the evidence "a very limited sample".

In this argument the evidence is about something broader "the council has voted for taxes"
and the conclusion/insinuation is about something more limited "Sherwood supports taxes"

[SkyeW831]

Thanks for the explanation. I now understand why E is right, but not why B is wrong. My line of thinking for choosing B was this: It is possible that the council's increase of taxes every year is unavoidable (perhaps because everyone else on the council supports higher taxes etc), even though it is undesired by Sherwood. Therefore, even though the council increased taxes every year, that doesn't mean that Sherwood isn't an opponent of higher taxes. Can someone tell me what's wrong with my thinking? Thanks!