Q16 - There is a difference between

[gyfirefire]

Could anyone help me better understand this assumption problem?

C="There is a difference between beauty and truth"
P1 = if no difference, most realistic=best, because the former is the most truthful;
P2 = many most realistic artworks are not among the best

i got the answer right since the rest are way off. But don't really understand the reason behind it. Just vaguely sensed that it needs to bridge from "best" in the P1 to "beauty" in the conclusion.

thanks a bunch in advance!

[bbirdwell]

Great instincts!

Let's look at exactly why (A) has to be true in order for the conclusion to work.

C: beauty ≠ truth

p: if beauty = truth --> most realistic = best
most realistic = most truthful
many most realistic ≠ best

It's easier to compare the premise/conclusion if they have a common element. Here, our conclusion has b=t and the conditional statement in our premise has b≠t. Let's contrapose it.
most realistic ≠ best --> beauty ≠ truth
(most truthful)

Now we can more clearly see the gap. Best must = beauty or this argument does not work at all!

This is what (A) says. For further clarification, you can try negating (A) to see how it affects the logic of the argument. What if the most beautiful are NOT the best? Well, then according to the statement above, it's still possible for truth and beauty to be the same thing.

[alex.chasan]

Thanks for breaking this one out...I understand the reasoning but I'm having trouble understanding why (D) is wrong here. If (D) says that beautiful --> best, isn't that enough to fill the gap?

[tamwaiman]

I have the same question, too.
Why (D) is not? Is it because (D) is lacking of "most"?
Thanks.

[ManhattanPrepLSAT1]

Great question!

The answer is that answer choice (D) is too strong. This is a necessary assumption question, not a sufficient assumption question. On necessary assumption questions you aren't looking to fill the gap completely. You're looking for what is required in order for the conclusion to have a chance of being true.

(A) states that beautiful art is the best. This answer choice only discusses beautiful art, and is weak enough to sit inside the gap without being more than what is required.
(D) states that everything beautiful is the best art. This is way too strong. It's not required that everything beautiful is the best art. Say for example a dear friend. She may be beautiful but that doesn't mean that she's art! And according to this answer choice if she's not art, then she can't be beautiful.

Does that clear this one up?

[interestedintacos]

This is what (A) says. For further clarification, you can try negating (A) to see how it affects the logic of the argument. What if the most beautiful are NOT the best? Well, then according to the statement above, it's still possible for truth and beauty to be the same thing.

That means that the answer choice is actually a sufficient assumption and not necessary. This question is almost identical to question #17 in section 1 of this test. On both of these questions we have the same type of argument, and on both we had necessary assumption stems with correct answer choices that were sufficient, but not necessary.

When we negate a necessary assumption the argument has absolutely no chance of holding--it's not that the argument can potentially be incorrect, it's that it has NO CHANCE of following. When we negate a sufficient assumption (but not necessary) then the argument doesn't follow, and may not follow, but still has a chance to follow.

This argument CAN ABSOLUTELY FOLLOW without answer choice A. Let's take a look:

IF B = T --> most T = the best

There is absolutely no necessity that we must have B on the other side of the conditional, just like we have truth. If the arguer shows, as he does, that the most truthful/realistic l art does not equal the best (all he needs is one counterexample to prove this, and in fact he has "many"), then the argument follows. If that side of the conditional is negated, the other side is negated, and we're done.

What the correct answer choice does is really add legitimacy to the argument--that it's not just some abstract conditional, but something that actually makes sense. If the best = the most B then we get this:

IF B = T --> most T = most B

Knowing that most T does not equal most B is enough, in any situation, to then say that T does not equal B. That's the heart of this. If one incarnation of A doesn't equal the corresponding incarnation of B, then we can say A doesn't equal B.

This is by no means a typical necessary assumption question. The correct answer isn't necessary in a conditional reasoning sort of way--it's necessary so that the argument goes from something that may be true but doesn't really have backing/legitimacy, to something that absolutely follows and makes a lot of sense.

Perhaps the test makers were trying to come up with a way to test "phrase switching" without testing conditional reasoning.

The nature of this one does in fact match up with other necessary assumption questions where we have to connect a new element in the conclusion with something that came before in the premises--and we have to do that so that the reasoning actually makes sense.

IF B = T --> most T = the best

So yes, again, while it's not necessary to change this formula at all for the argument to be valid from a formal perspective, to actually make sense of things (to add legitimacy to the logic)--to show why "most T= the best" would actually be connected in some way to B=T--we would need something like we get in the answer choice.

[interestedintacos]

To better understand what I'm saying take a look at Section 2, Question 17. We are dealing with essentially the same thing. The test makers were testing whether you could catch up to the phrase switching, but not your knowledge of conditional reasoning. In that one the logic goes like this:

A ≠ C

Thus, I ≠ C

The "necessary" assumption was essentially A = I.

Of course, they twisted the words on this one to make it seem even more like it was a conditional reasoning question. We're led to believe that they're saying ~(A-->C) rather than A ≠ C, and even the answer choice says A requires I, instead of A=I. But if you look at this one and the one here (in section 2) I think it becomes clear they're thinking something like A ≠ C.

If, on the other hand, you looked at it from a conditional reasoning perspective, then it was not necessary to assume A-->I; it would only be necessary to show that in at least one case A involved I, not that A requires I period. Again that leads me to believe they were seeing it as I've illustrated above, and they simply changed words around to add more confusion--namely to get people to make erroneous assumptions based on expecting a bread and butter conditional reasoning question.

In both that one and this one there was an attractive incorrect choice like D here: a choice that was based on the false assumption that we were dealing with conditional reasoning, and that in any case gets it backwards so it doesn't play a necessary or sufficient role in the argument.

[ManhattanPrepLSAT1]

That means that the answer choice is actually a sufficient assumption and not necessary.

The reason why you're seeing so many Sufficient Assumption looking answer choices on these Necessary Assumption questions is that there is a gap in the argument and the the answer choice bridges just the gap, but no more.

In this example I see a very elegant argument:

~D ---> (MR ---> Best)
MR some ~Best
------------------------
D

(Notation Key: D = difference, MR = most realistic, Best = Best)

What's so wonderful about this argument is that there is no gap. It's the straight forward application of the contrapositive. At the broadest level the argument is actually valid. Where this argument gets into trouble is in the middle.

Apparently, we know that the "most realistic would be the best" since "the most realistic are the most truthful." The gap in this argument is within the subsidiary argument here.

MR ---> MT

---------------
MR ---> Best

(Notation Key: MR = most realistic, Best = Best, MT = most truthful)

So the gap in the reasoning is

MT ---> Best

The most truthful works are the best works. Unfortunately, after glancing at the answer choices you see that nothing says, "the most truthful works are the best works." And here's where the genius of the test writer shows, this subsidiary argument was taking place under the condition that there is no difference between beauty and truth. Note that the sentence where you find this argument begins by limiting the scope to what happens when there is no difference between beauty and truth.

So we can substitute beauty for truth, and arrive at the assumption of the argument as it's stated in the answer choices

MBeautiful ---> Best

The most beautiful works are the best - perfectly expressed in anser choice (A).

I understand your point about PT49, S2, Q17. But that one is also testing conditional logic. I think the reason why the answer choices sound Sufficient is that both arguments essentially rely on the refutation of a conditional statement.

To undermine the notion that the "most realistic would be the best" the argument needs to show that some of the most realistic are not among the best. Likewise, on the other argument, in order for the argument to conclude that "it's not true that intelligence would establish conscious awareness," the evidence would need to establish that some things with intelligence do not have conscious awareness. In both cases the arguments attempt to refute a claim, and I suspect that the reason these answer choices are actually necessary deals with the fact that the arguments seek to refute a claim at some point.

What do you think?

[skapur777]

Here is my explanation, tell me if I'm right please

They say there must be a difference between beauty and truth.

Because, if not, the most realistic pieces of art would be the best as well...since they are the most truthful. Here they are basically saying that the most truthful would qualify as the best. However many of the most truthful are NOT among the best.

My confusion here was...what is the connection between most truthful and 'best'. In other words...why did they say most truthful is the best? Because, presumably they are saying that the most beautiful are the best.

And if beauty is the SAME as truth, then the most truthful=most beautiful and thus most truthful=the best.

By saying that the most truthful are the best yet the most beautiful are, they are saying there is an inherent difference between the two.

Am I on the right path?

[ManhattanPrepLSAT1]

They say there must be a difference between beauty and truth.

Because, if not, the most realistic pieces of art would be the best as well...since they are the most truthful. Here they are basically saying that the most truthful would qualify as the best.

Careful. The are assuming that the most truthful are the best, they are not actually saying it. But so far, so good.

However many of the most truthful are NOT among the best.

Where do you see this in the argument?

My confusion here was...what is the connection between most truthful and 'best'. In other words...why did they say most truthful is the best?

Again where do you see this in the argument? In fact, that's the assumption of the argument. It just also happens that if there were no difference between beauty and truth, then that would imply that the most beautiful artworks are the best.

Hope that helps!

[skapur777]

Here was my reasoning:

The argument says that the most realistic would be the best, since the most realistic are the most truthful.

BUT many of the most realistic are not among the best.

It says the most realistic would be the best because they are the most truthful.

Most realistic>most truthful>best.

The assumption being that most truthful=the best. Is this correct?

Yet the most realistic are not the best. Since most realistic=most truthful, the most truthful are not the best either.

According to choice (A), if some of the most beautiful artworks are not the best, just like some of the most truthful are not the best then there could be no difference between the two.

But if choice A is taken as is, that the most beautiful artworks are the best yet the most truthful are not (at least some of them) then there is a much better chance that there is some sort of difference.

[ManhattanPrepLSAT1]

According to choice (A), if some of the most beautiful artworks are not the best, just like some of the most truthful are not the best then there could be no difference between the two.

For the most part, your logic looks pretty good. Can you explain how you got this part here though? Answer choice says that the most beautiful artworks are the best artworks, so how do you say that according to answer choice (A), ... there could be no difference between the two?

[superduperchong]

I don't know if the way I did it was too simplistic (or confusing), but I got (A) because of the words "as well" in the second sentence.

"as well" indicates that there is something that is already considered the best.

So finishing off "as well" in the second sentence would turn it to something like this: If there were no difference between beauty and truth, then the most realistic piece of art would be the best--along with the most beautiful pieces of art (which are considered the best).

But since the most realistic pieces of art are not the best, and the most beautiful pieces of art are considered the best, there is a difference between beauty and truth.

Hope that helps!

[geverett]

Hey Matt,
So does A work b/c it's taking a subset of beautiful artworks "most beautiful" and saying they are the best. Whereas D is saying that all beautiful artworks are the best which is more than we need?

Would A also be right if it said "Some works on the lower side of the beauty spectrum, which are nevertheless considered beautiful, are the best artworks. Thoughts?

[dean.won]

Can you check if my reasoning is correct?

Stim : if B&T were the same then the most realistic (most truthful) would be the best. BUT SOME of the most realistic are NOT the best thus B&T are not the same.

Assumption : Some artwork that is NOT the most realistic ARE the best.

ie. Some of the best are not the most realistic.

Could A still be correct if it said..
"Some beautiful art are the best"
"Some unrealistic art are the best"

What tripped me up at first was the "most beautiful"
Didnt think it was necessary but it was the best answer of the choices

[samuelfbaron]

Con: Beauty cannot equal truth

Premise: If beauty equals truth --> the most realistic artworks would be the best cause the most realistic are the most truthful.

Premise: But many of the most realistic artwork (which are the most truthful) are not among the best.

So there is a gap in the logic. Beauty cannot equal truth because the most realistic pieces of art are not among the best. If there were no difference between beauty in truth then it would be possible for the most realistic to be among the best.

(A) Fills the gap, solidifying the argument.It is necessary to assume that the most beautiful are the best. If this not were the case, then the conclusion would be tenuous.

[pewals13]

Premise: If beauty equals truth —> The most truthful artworks would be the best (because the most realistic are the most truthful)

Premise: The most truthful artworks are not the best

Conclusion: Beauty does not equal truth

Your only real competitors here are (A) and (D)

(A) The most beautiful artworks are the best artworks.

This is necessary to make the argument work.
If Beauty = Truth —> Most Truthful = Best
Since Most Truthful /= Best
Conclusion: Truth /= Beauty

You need to translate Truthful /= Best into Truthful /= Beauty

(D) Only the best artworks are beautiful.

Beautiful —> Best

This answer choice would be sufficient, but it is not necessary for everything that is beautiful in the world to also be art for the argument in the stimulus to work.