#25 - Some twentieth-century art is great art. All great art

[SherryZ]

Hi there, thank you for your help!!

After read Lesson 8 Formal Logic Sec, I can eliminate answer choices A, B and E. However, I don't know why D is wrong and C is correct PLEASE HELP

--Sherry

[Steve Stein]

Hi Sherry,

It's great that you were able to narrow that one down to two options--that means that you must have done some effective diagramming! It would be helpful to know what diagrams you were able to draw from the stimulus, then we can assess the answer choices--let us know--thanks!

~Steve

[SherryZ]

Dear Steve,

Thank you for your reply. I have following references, please add more or correct any of my mistakes!

1. 20C Art Great
2. Great Original Ideas (Hence, G OI & G OI)
3. Not influential Not Great (Hence, G Influential)
4. Combine 1&2, we can infer that 20C Art OI (Answer B)
5. Combine "20C Art Great" & "G Influential", we can infer that 20CA Influential
6. Combine "G OI" & "G Influential", we can infer that OI Influential (Answer A)
7. Combine "20CA Influential" & "20C Art OI", we can know 20C Art Influential AND have OI (answer E)

However, I cannot make inference to decide C and D which one is right, which one is wrong

Thanks again and looking forward to your reply!

----Sherry

[KelseyWoods]

Hi Sherry,

Excellent diagramming and inference-making!

Now let's diagram answer choices (C) and (D)....both of them start with an "only" which is a necessary indicator.

The diagram for answer choice (C) would be:


Influential Original Ideas


Based on your diagramming, you know that some influential art involves original ideas but we can't say that ALL influential art involves original ideas. So answer choice (C) does not follow logically from the statements in the stimulus and is therefore our correct answer.

Answer choice (D), on the other hand, looks like this:


Influential
Great Art +
Original Ideas


This comes directly from your diagrams (points 2 & 3).

Hope this helps!

Best,
Kelsey

[SherryZ]

Dear Kelsey,

Thank you so much for your help! It is very helpful! Wish me luck in Dec LSAT


Sincerely,
Sherry

[Sherry001]

Hello ;
I have 0 idea why c is wrong. I see how all the other answers work , just not sure about c.

Q type : cannot be true / must be true EXCEPT.

20cen--> great art
Great art -> original idea
Great art -> influential

C) influential-> original Idea

Why can't I do this? Couldn't this be true ? ( I do this kinda linking in justify questions all the time ) Great art -> Influential -> original idea

Thanks very much
Sherry

[Steve Stein]

Hey Sherry,

That's a good question, and you've diagrammed almost everything correctly. The first sentence provides that some 20th century art is great art; your first diagram suggests that all 20th century art is great art, which is not suggested by the passage.

Your next two diagrams are accurate, and together indicate that all great art involves original ideas and is influential.

The question that follows the stimulus is requires you to find the one answer choice that doesn't follow logically from the stimulus. This means that the four incorrect answer choices would be those that can be logically concluded based on the stimulus.

Answer choice (C) claims that the only kind of art that is influential is the kind that contains original ideas—that influential art is limited to art containing original ideas. While this could be true, as you alluded to, it is not dictated to be true based on the stimulus.

I hope that's helpful! Please let me know whether this makes sense--thanks!

~Steve

[bk1111]

Hello, I don't understand how answer choice A is a valid inference. I thought it was not possible to combine two ALL statements:

Great ----> Original
Great ----> Influential

[Francis O'Rourke]

Hi bk,

You’re right that the two statements you listed cannot by themselves tell us much about the relationship between original and influential art. However, if you broaden what you are looking at just a little bit we can discover a small connection between them.

The first sentence tells us that there exist some works of 20th Century art that are great. Taking the two statements which you provided, what does that tell you about some pieces of 20th Century Art? Well if it’s great, it must be both Original and Influential. So if we have one piece of great 20th Century art that we can call great, it must also be influential and involve original ideas. Hence answer choice (A): there is some artwork that has both of these qualities.

[rgold3]

Hi-this discussion says that D is the correct answer, but my answer key shows C being correct. Can you please provide some clarification here?