Q6 - Books about architectural works, unless

[cdjmarmon]

I got the question right, however, when I was reviewing I decided to right down the conditional logic. In doing so I cannot seem to arrive to the conclusion. I used what I learned in the Logic Reasoning books were you negate the unless part and I just can't seem to make this work for me on this question. To me the conditional of the first sentance is:

Intended for a general aud. ----> Include both utility and aesthetic appeal

Since the unless has a not already in it I took that as it should be removed when applying the rules which is how I got to intended for a general aud.

[timmydoeslsat]

That definitely is an awkward and unusual sentence.

The unless portion is interrupting the full statement of what is being said, so it can be diagrammed as follows:

Books about arch works ought NOT to include discussions of utility and aesthetic appeal of each building they consider ---> ~Intended for a general audience

And you simply listed the contrapositive of what I had, which is equally valid.

Do not let the already negated unless part confuse you.

A unless ~B

~A ---> ~B

B--->A

[bbirdwell]

Books about arch works ought NOT to include discussions of utility and aesthetic appeal of each building they consider ---> ~Intended for a general audience

And you simply listed the contrapositive of what I had, which is equally valid.

Careful there! The AND on the sufficient side must also be negated.

Intended for a general aud. ----> Include both utility and aesthetic appeal

Since the unless has a not already in it I took that as it should be removed when applying the rules which is how I got to intended for a general aud.

Yep. Not + Not = Yep. So when negating a "not," simply remove it.

So we have:
intended for general audience --> utility & aesthetics

The important part comes next. We might be tempted to think this:
no utility OR no aesthetics --> flawed

It's important to remember, though, that we're specifically talking about those books intended for a general audience.

So a more accurate rendering would be this:
intended for general audience AND [no utility OR no aesthetics] --> flawed

Next:
Morton = "utility & no mention of breathtaking masterpiece"

Question:
What do we need in order to conclude "Morton --> flawed"???

Two things.
1. We need to prove that he's talking to a general audience, because if he's not, we're out of our league (scope) -- the only books we know anything about are those designed for general audiences.

2. We also need to prove that not calling that one particular ceiling a masterpiece is equivalent to "no discussion of aesthetics."

No answer choice does 2. (C) does 1.

Notice the trap (E), which attempts to do #2. We still have NOT established, however, that the author fails to discuss the aesthetics of that palace. The only thing we know is very, very specific: that the author did not call the main hall of said palace a breathtaking masterpiece.

Hope that simplifies things!

[nandy_millette]

My reasoning for this question was a bit different:

If book intended for general audience--> must discuss utility and aesthetics, otherwise flawed

C; Morton book is flawed
S; It discussed utility but not aesthetics

Question: what do we need to reach this conclusion?

My reasoning was this: If the sufficient requirement fails which in this case is "intended for a general audience" then the conditional logic statement falls apart (which is something I learnt and use regularly for Logic Games)

So in this case if the sufficient assumption " intended for a general audience" fails then we cannot apply the conditional statement rule to evaluate the conclusion which is what Answer C tells us.

My issue with this question is that I am not sure how to classify the question stem. During the test I treated it as an evaluate the argument conclusion hence my reasoning strategy used above but now I am thinking that it can also be a necessary assumption question. Your thoughts?

[WaltGrace1983]

My reasoning for this question was a bit different:

If book intended for general audience--> must discuss utility and aesthetics, otherwise flawed

C; Morton book is flawed
S; It discussed utility but not aesthetics

Question: what do we need to reach this conclusion?

My reasoning was this: If the sufficient requirement fails which in this case is "intended for a general audience" then the conditional logic statement falls apart (which is something I learnt and use regularly for Logic Games)

But we don't KNOW if the sufficient condition has failed or not. That is the assumption!

So in this case if the sufficient condition " intended for a general audience" fails then we cannot apply the conditional statement rule to evaluate the conclusion which is what Answer C tells us.

My issue with this question is that I am not sure how to classify the question stem. During the test I treated it as an evaluate the argument conclusion hence my reasoning strategy used above but now I am thinking that it can also be a necessary assumption question. Your thoughts?

This is a necessary assumption question ("it would be necessary to establish...")

The conditional looks something like this:

(~(discuss both utility and aesthetic appeal) & intended for general audience) --> flawed

Now we know* that we satisfied one of two elements of the entire sufficient condition.

The first element we satisfied is ~(discuss both utility and aesthetic appeal). We know that both were not discussed.

HOWEVER, we still need to satisfy the other element of the sufficient condition, (intended for general audience). If this isn't so, that is, if the book was NOT intended for a general audience, then the conditional statement does not matter. If the conditional statement doesn't matter, then we cannot conclude (flawed) on the basis of this conditional statement alone.

But the argument is assuming the other element of the sufficient condition. The argument is assuming (intended for a general audience). That is why (C) is correct.

*I am assuming that not talking about the main hall of the palace would be enough to claim that aesthetic appeal was not discussed. This was actually the assumption that I was looking for when I was doing this.

[Mab6q]

My reasoning for this question was a bit different:

If book intended for general audience--> must discuss utility and aesthetics, otherwise flawed

C; Morton book is flawed
S; It discussed utility but not aesthetics

Question: what do we need to reach this conclusion?

My reasoning was this: If the sufficient requirement fails which in this case is "intended for a general audience" then the conditional logic statement falls apart (which is something I learnt and use regularly for Logic Games)

But we don't KNOW if the sufficient condition has failed or not. That is the assumption!

So in this case if the sufficient condition " intended for a general audience" fails then we cannot apply the conditional statement rule to evaluate the conclusion which is what Answer C tells us.

My issue with this question is that I am not sure how to classify the question stem. During the test I treated it as an evaluate the argument conclusion hence my reasoning strategy used above but now I am thinking that it can also be a necessary assumption question. Your thoughts?

This is a necessary assumption question ("it would be necessary to establish...")

The conditional looks something like this:

(~(discuss both utility and aesthetic appeal) & intended for general audience) --> flawed

Now we know* that we satisfied one of two elements of the entire sufficient condition.

The first element we satisfied is ~(discuss both utility and aesthetic appeal). We know that both were not discussed.

HOWEVER, we still need to satisfy the other element of the sufficient condition, (intended for general audience). If this isn't so, that is, if the book was NOT intended for a general audience, then the conditional statement does not matter. If the conditional statement doesn't matter, then we cannot conclude (flawed) on the basis of this conditional statement alone.

But the argument is assuming the other element of the sufficient condition. The argument is assuming (intended for a general audience). That is why (C) is correct.

*I am assuming that not talking about the main hall of the palace would be enough to claim that aesthetic appeal was not discussed. This was actually the assumption that I was looking for when I was doing this.

Hey Walt, nice analysis. I wanted to add that I don't think we need to make the last assumption. I think the question purposely leaves it vague to serve as a red herring, which makes some of the other answer choices tempting.

Bests,

[judaydaday]

Yep. Not + Not = Yep. So when negating a "not," simply remove it.

So we have:
intended for general audience --> utility & aesthetics

The important part comes next. We might be tempted to think this:
no utility OR no aesthetics --> flawed

It's important to remember, though, that we're specifically talking about those books intended for a general audience.

So a more accurate rendering would be this:
intended for general audience AND [no utility OR no aesthetics] --> flawed

Next:
Morton = "utility & no mention of breathtaking masterpiece"

Question:
What do we need in order to conclude "Morton --> flawed"???

Two things.
1. We need to prove that he's talking to a general audience, because if he's not, we're out of our league (scope) -- the only books we know anything about are those designed for general audiences.

2. We also need to prove that not calling that one particular ceiling a masterpiece is equivalent to "no discussion of aesthetics."

No answer choice does 2. (C) does 1.

Notice the trap (E), which attempts to do #2. We still have NOT established, however, that the author fails to discuss the aesthetics of that palace. The only thing we know is very, very specific: that the author did not call the main hall of said palace a breathtaking masterpiece.

Hope that simplifies things![/quote]

So to clarify, in the second sentence "If they do not, they are flawed" is "they" referring to the ENTIRE conditional statement in the sentence immediately preceding it?

Intuitively I understand why it would be:

GA + /discussion -> flawed

However, mechanically I don't understand how this works since the sentence before is only saying:

GA -> discussion

Is it that "they" refers to books intended for general audience? and "do not" is what negates discussion .

But how does lead to the conditional statement become an "and" sufficient condition?

[christine.defenbaugh]

I'm so glad you posted this question, judaydaday!

This is where conditionals get a little whacky - nested conditionals.

There are three ways of understanding the first two sentences of this stimulus and (this is important) - all of them are totally correct. Here goes:

1) BACKGROUND CAVEAT
So, we could read the "unless they are not intended for a general audience" as a background caveat that could neutralize anything we're saying. With that original 'unless' statement, the author tells us that if the books are non-GA, all bets are off. But under the heading of 'general audience' books, the rule is:

if not (utility-discussion AND aesthetic-discussion) --> flawed

But for this rule to even apply in the first place, we'd need Morton's book to be GA.

2) FLAWED JUST MEANS RULE-BREAKERS
We could also simply read the first sentence as a regular conditional, using what we know about translating "unless" statements.

IF GA --> should include both utility-discussion AND aesthetic-discussion

The "if they do not" might be accurately read as "if they break this rule". So, if books break this rule, they are flawed. The only way to break this rule is for a book to be 1) GA AND 2) fail at the discussions requirement. If a book isn't GA, it can't break the rule.

3) "THEY" PROBABLY MEANS THE BOOKS THE AUTHOR IS ACTIVELY DISCUSSING

And lastly, the pronoun "they" in the second sentence should probably simply be read as "general audience books", since the author is only laying down the law for those books. Reading the second sentence to only be referring to GA books leads to a notation of:

If GA don't include utility-discussions AND aesthetic-discussions --> flawed
or
IF GA AND fail discussions requirement --> flawed

Note: these two statements are logically identical, in the same way that these two statements are:

1) If cats don't purr, they are evil.
2) If you are a cat AND you do not purr, then you are evil.


All of these are perfectly reasonable interpretations of the language in the first two sentences, and interestingly, all three are logically valid (and functionally equivalent). The most important thing to remember here is that while getting to the conditional notation can be super helpful for mental organization, we're still reading human language to begin with. We need to read that language (i.e., pronouns) in ways that make sense! It would be crazypants for the author first give a rule for what GA books should do, carve out a clear exception for non-GA books, then turn right around in the second sentence and say that ALL books are flawed, even non-GA ones, if they don't do that thing. If that's what the author meant, he'd need to make that SUPER CLEAR - because that would be a weird-as-heck thing to do.

Moral of the story: start by reading each sentence for rational meaning, THEN translate those pieces into formal logic notations!

Does that help clear things up a bit?

Also, Mab6q, very close!

*I am assuming that not talking about the main hall of the palace would be enough to claim that aesthetic appeal was not discussed. This was actually the assumption that I was looking for when I was doing this.

Hey Walt, nice analysis. I wanted to add that I don't think we need to make the last assumption. I think the question purposely leaves it vague to serve as a red herring, which makes some of the other answer choices tempting.

The AUTHOR needs to make that assumption, but we don't. So, it's not a red herring, exactly - it's totally in scope and on target. It would have been an awesome answer choice, if only the LSAT had seen fit to write one that matched. Some of the wrong answers, though, are absolutely tempting because they touch on superficially similar ideas, but they all get it wrong.

We don't need to assume it, though, simply because this is a necessary assumption question - there may be many assumptions that are necessary for the argument to work! The correct answer just has to address one of them.

Hope this was helpful for both of you!

[judaydaday]

Thank you! That was very helpful.

[kimhyungjoon]

Stem: seems unorthodox, but it amounts to a necessary assumption question. The stem provides the conclusion that is not in the stimulus:
Morton's book (on Italian Baroque palaces) is flawed

Stimulus
Premise 1: General books about architectural works that don't discuss both utility and aesthetics are flawed
Premise 2: Morton's book discusses utility for sure but in one occasion failed to discuss aesthetics

Prephrase
1. Morton's book is written for a general audience
2. Nowhere in his book does Morton discuss aesthetics

Answer choices
A: Accuracy is not a criterion in the stimulus
B: Again, beyond the scope of the criteria for flawed architecture books
C: This is one of the prephrased answers
D: This is insufficient because the criteria explicitly states aesthetics must be discussed for "each of the buildings they consider".
E: This is the same as D

Conditionals
1. Architectural books should include discussions on both utility and aesthetics unless intended for non-general audience
Contrapositive of 1: If intended for general audience, architectural books should include discussions on both utility and aesthetics
2. If architectural book doesn't include discussions on both utility and aesthetics, then it is flawed + not intended for general audience
Contrapositive of 2: If architectural book is not flawed AND/OR intended for general audience, it includes discussions of both utility and aesthetics

Lessons
This is one of those "tricky despite appearing early on" questions. You may indeed have forgotten about the "unless not for general audience" part of the stimulus by the time you were prephrasing.

[SJK493]

So a more accurate rendering would be this:
intended for general audience AND [no utility OR no aesthetics] --> flawed

Bbirdwell, how did you get from No Utility or No Aesthetics → Not Intended for General Audience to adding flawed and the multi-conditional above?

[WendyQ765]

In this question, we know from the premises:
General Audience → Utility + Aesthetic,
and
/U or /A → Flawed.

The conclusion is
U+/A→Flawed.
But the conclusion must rest on the premise that M-book is intended for a general audience. Because if it’s not intended for GA, then the premise doesn’t occur and we cannot conclude anything from the premise. So answer choice C is right.
Answer choice is wrong because it’s not necessary for the palace discussed at length is the most ……
We need to know that it’s the only one of aesthetic appeal but not the most important one.