Q15 - There are two supposedly conflicting

[axelleklincke]

Could you please explain this problem- why the wrong answers are wrong and A is correct. Thanks!

[giladedelman]

Yes indeed, I believe I can!

So let's identify the argument core. Notice that this argument follows a pretty common LSAT structure: many people believe this; however, I think something different; now here's my reason.

In this case, many people believe these two hypotheses are conflicting: that a great national leader can't both shape and react to public opinion. The argument says, hey, that's not actually the case. As evidence, it points out that all leaders that have had success getting programs passed display both traits.

So our core looks like this:

all leaders successful in getting programs passed have both these traits ----> these traits not mutually exclusive for great national leaders

I think the gap between premise and conclusion should be staring us in the face at this point! The premise is talking about leaders who got legislatures to pass their programs, while the conclusion is about great national leaders! How do we know these are the same thing? We don't. The argument assumes that these are the same.

That's why (A) is correct. The argument depends on assuming that having success in getting programs passed by the legislature means you're a great national leader.

(B) sort of helps the argument, I guess, by suggesting that these two traits are linked, but it is absolutely not necessary to assume that you can't possibly do one without the other.

(C) is incorrect because the issue is whether shaping and reacting to public opinion are mutually exclusive, not whether they're necessary for leading.

(D) is just out of scope -- where does "good rapport" with the legislature come in here? (It doesn't.)

(E) is out of scope, too. The argument involves reacting to public opinion, but not being "swayed" by it.

Does that clear this one up for you?

[jamiejames]

I've noticed with these questions, that if I can identify an aspect of the conclusion that isn't in the premise, the correct answer choice will contain this aspect, where incorrect answer choices will not contain this information. Is this a good way of attack necessary assumption questions?

[timmydoeslsat]

I've noticed with these questions, that if I can identify an aspect of the conclusion that isn't in the premise, the correct answer choice will contain this aspect, where incorrect answer choices will not contain this information. Is this a good way of attack necessary assumption questions?

It is a great way to attack.

Example:

My pencil is green.
____________________
Therefore, my pencil is expensive


I have talked about expense in my conclusion and nothing about it in the premises.

I, obviously, have assumed [green ---> expensive]

This assumption is both sufficient and necessary.

Of course, this is not always the case where an assumption is both sufficient and necessary.

Your point about essentially a mismatch from the evidence given to the conclusion reached is really the fundamental aspect of a necessary assumption. For an idea to be discussed in the conclusion, yet not in the evidence, depends on that idea being tied with the evidence in some fashion.

[giladedelman]

Yes, good stuff you guys--when we see a clear mismatch between the premise and the conclusion, i.e., the premise is talking about A and then in the conclusion B comes out of left field, it's a good idea to look for an assumption that links these two ideas. But remember that because necessary assumptions will often be negating competing possibilities, the answer might not look exactly how we expect it to, so we can't use this method robotically. It's a good way to prime ourselves for the answers, but it's not a magic formula.

[wguwguwgu]

That's why (A) is correct. The argument depends on assuming that having success in getting programs passed by the legislature means you're a great national leader.

I still can't see why A is necessary. It still feels like rather a sufficient condition that fully enables the argument???

Basically, we only need something that asserts some overlap between the two groups "great national leaders" and "leaders getting their bills passed", right? Wouldn't something like this sound like a real necessary assumption?
"At least some great leaders successfully get their bills passed."

many thanks in advance!

[doug.feng]

That's why (A) is correct. The argument depends on assuming that having success in getting programs passed by the legislature means you're a great national leader.

I still can't see why A is necessary. It still feels like rather a sufficient condition that fully enables the argument???

Basically, we only need something that asserts some overlap between the two groups "great national leaders" and "leaders getting their bills passed", right? Wouldn't something like this sound like a real necessary assumption?
"At least some great leaders successfully get their bills passed."

many thanks in advance!

A is necessary because there is a slight shift from hypotheses that make a "great leader" (premise) to "successfully getting their legislature passed" (conclusion). We need an assumption that would link this shift from one to the other.

[tommywallach]

Great explanation, Doug!

-t

[inesa909]

For this question, it is very clear to me why the correct answer is correct. However, in the 10 Real LSATS grouped by Question Type book, the explanation for why (D) is wrong is very confusing to me. It says that (D) "brings in a new concept ("rapport"), which dooms any answer on a Sufficient Assumption question...". When I took the practice test I chose D and I'm confused what was meant by this part of this explanation especially since it is a necessary assumption question.

[maryadkins]

Hmm. Interesting. Well, you're right, it's not a Sufficient Assumption question. It's a Necessary Assumption question. So I'd ignore that explanation and go with Gilad's which is essentially the same thing (out of scope) but doesn't call the question the wrong type:

(D) is just out of scope -- where does "good rapport" with the legislature come in here? (It doesn't.)

[civnetn]

I think it's important to realize why this problem has been screwing several of us over (myself included)

The problem with this question is it's very easy to not fully realize the conditional relationship described by the first two sentences

The 2nd Sentence States: "One is that such leaders Successfully Shape Public Opinion..."

If like I did, you interpreted these this to mean:

Great National Leader ---> Successfully Shape Public Opinion

Great National Leader ---> Adept Reaction to Public Opinion

Then great, but we both forgot to look at the first sentence, which says, "There are two supposedly conflicting hypotheses as to what makes for great national leaders."

I didn't even realize this, but this argument is actually straight up telling us that there's an assumption here. Because how to you conditionally represent this sentence? Like this:

Successfully Shape Public Opinion ---> Great National Leader

Adept Reaction to Public Opinion ---> Great National Leader

[SriyaS366]

I also chose (B) when I first did this question. However, I think the reason why (B) is incorrect is the important distinction between what the conclusion actually asserts and answer choice (B). All the conclusion says is that treating these hypotheses as mutually exclusive is a mistake. However, this does not necessarily mean that we should consider them to be mutually inclusive. The conclusion says the two hypotheses are not mutually exclusive. What this means is that shaping public opinion and being adept in reacting to it should not be treated as not including each other. This is different from the meaning of mutually inclusive, which means one includes the other. This is what tripped me up on (B) because I assumed that if the relationship between the two is not mutually exclusive, then it is necessarily mutually inclusive. However, this is not a correct assumption to make. Therefore, since this is a necessary assumption question, (B) would then be incorrect.