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 Adam Tyson
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#68468
Regarding questions about conforming to principles and the proper use of conditional analysis, PB410 asked:
To add to my earlier question, in prep test 22.2 Q#18, I found an example of my question. Answer choice C states the contrapositive, where the negated conditions allow one to arrive at the negated necessary condition, while answer choice D states the necessary conditions and arrives at the sufficient condition. So is it best to seek out the answer choices leads to the necessary condition?

the diagrams I have for question 18, prep test 22, section 2 are
Truly great -----> original and Far reaching influence on artistic community
and
NOT original or NOT far reaching influence -----> NOT truly great.

So just go for the answer that arrives at NOT truly great?
Is there a case where the correct answer could be something like, "Peruvian paintings from the 18th century are truly great. They are both original in their use of religious subject matter, and their methods of painting the human form have been regularly adopted by succeeding artists."

Thanks
 Adam Tyson
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#68469
Answer C in this question actually wasn't a contrapositive, PB410, nor was your example about Peruvian paintings. Both of those were actually Mistaken Reversals, where the presence of the necessary conditions (far reaching and original) is being used to prove the presence of the sufficient condition (great art). A contrapositive is when the necessary condition does NOT occur, and the author concludes that the sufficient condition cannot occur. That's what happens in answer B, the correct answer here, and in your perfect diagram.

The correct answer to a "conforms to the principle" question will, one way or another, follow the rule. Either the sufficient condition will occur, and the author will properly conclude that the necessary must occur, or else the necessary condition will NOT occur, and the author will correctly conclude that the sufficient condition cannot occur. Usually, when the principle has multiple necessary conditions and a single sufficient condition, we will see the contrapositive in the correct answer. Also usually, when there are multiple sufficient conditions and a single necessary condition, we will follow the original rule in the correct answer, with both sufficient conditions occurring and the author concluding that the necessary condition must occur. There are exceptions, of course, because this is the LSAT and they don't want us to get too comfortable with their patterns, but they still generally follow those patters and we should expect them most of the time.

I hope that helps!
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 yenisey
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#96109
Can you please tell, is this question most strongly supported or principle question?
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 katehos
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#96119
Hi yenisey!

This is a Most Strongly Supported (aka Must Be True with a slight reduction in degree of certainty needed) Principle question. Basically, it's both! Principle questions are not one specific question type, rather, they are an "overlay" that appears in a variety of question types.

I hope this helps :)
Kate
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 Kenyambo
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#101862
I am still unclear as to why C is the wrong answer. It shows both aspects of the rule established … original and influence.

Can someone help me out ? In more simplistic terms.
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 Jeff Wren
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#101890
Hi Kenyambo,

The first thing to realize is that this question involves a principle in the stimulus and then asks for an answer that follows the principle. A principle is a broad rule that is often conditional in nature, and the principle in this stimulus is also conditional.

It is critical to correctly understand how the conditional relationship works in this principle.

The stimulus states that "to classify a work of art as truly great, it is necessary that the work have both originality and far reaching influence upon the artistic community."

The use of the word "necessary" tells us that "originality" and "far reaching influence" are the necessary conditions, while "to classify a work of art as truly great" is the sufficient.

In other words, the principle is saying that:

IF a work of art is truly great, THEN we know that it has originality and far reaching influence.

This could be diagrammed

WOTG (work of art truly great) -> O (originality) and FRI (far reaching influence)

However, that does NOT mean that if a work of art has originality and far reaching influence, then it must be a truly great work of art. That would be an error of reasoning that we call a Mistaken Reversal.

With this in mind, it is important to note that we can never prove that a work of art is truly great based on this principle, so any answer that concludes that a work of art is truly great will be wrong.

This is exactly what happens in Answer C. This answer concludes that the originality and far reaching impact of the music is enough (i.e. sufficient) to consider these to be truly great works of art. While Answer C has the three terms in that appear in the principle as you point out, they are not used in the correct order.

Here's an example that may help show the problem.

Imagine that we are given a conditional statement in the stimulus that says, "If someone has a banana, then that person has a piece of fruit." (This isn't a principle, but it is a conditional statement that should be easy to follow based on real life.)

Answer C basically would say, "John has a piece of fruit and that is enough to tell us that he has a banana." Obviously, knowing that John has a piece of fruit does NOT prove that he has a banana. In the same way, in the question, knowing a work of art is original and has far reaching influence does NOT prove that it is truly great. The arrow only goes in one direction from the sufficient to the necessary. Answer C is going backwards against the arrow (a Mistaken Reversal).

If you would like more information on principle questions, they are covered in lesson 8 of The PowerScore LSAT Course and chapter 21 in The Logical Reasoning Bible. If you would like more information on conditional reasoning, it is covered in lesson 2 of The PowerScore LSAT Course and chapter 6 in The Logical Reasoning Bible.

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