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 James Finch
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#65701
Hi Gretchen,

We actually don't need to use the Assumption Negation technique to see that (A) is correct; instead, it's easier simply to Prephrase the logical gap and apply that to our answer choices to see which one fits. With answer choice (A), we'll simply use the Unless Equation to diagram the given conditional and see if that or its contrapositive fits our Prephrase.

Here the Prephrase is:

Performed Regularly :arrow: Popular

Answer choice (A) gives us:

Popular :arrow: Performed Regularly

and it's contrapositive,

Performed Regularly :arrow: Popular

Fits like a glove, so this is the correct answer.

Hope this helps!
 nosracgus
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#80407
Hi - I had trouble with the conditional relationship in this stimulus, but I was able to rule out E because I didn't feel like it was linking the rogue element in the conclusion that "no play will be popular several centuries from now" whereas A is doing exactly that.

Is that a valid way to rule out E? Just want to be sure I'm not using this technique incorrectly. Thanks!!
 uchong
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#80736
I have a question about the conditional relationship in this question. In the original explanation post, there is a diagramming of the relationship between performed regularly (PR) and skillfully explore human nature (SEHN), which states that SEHN is the necessary condition. However, I thought "only" introduces necessary conditions. In the stimulus, "only" introduces PR (e.g. "the only plays that continue to be performed regularly over many decades and centuries"). Why is PR not the necessary condition in this relationship?
Administrator wrote:Complete Question Explanation

The critic reaches this conclusion based on a rule, that “the only plays that continue to be performed regularly over many decades and centuries are those that skillfully explore human nature.” This is a conditional rule, which we can diagram as:

PR = performed regularly over many decades and centuries
SEHN = plays that skillfully explore human nature
  • Sufficient ..... Necessary

    PR ..... :arrow: ..... SEHN
 Adam Tyson
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#81237
nosracgus, your analysis of answer E is correct! It fails because it never deals with the important issue of popularity, which is at the heart of the conclusion.

uchong, you have made a very reasonable mistake, falling into the trap of the confusing construction that begins with "the only." There are two ways of dealing with that phrase, and talking about them both at the same time can cause heads to spin a little, but I am going to give it a try. Both of them depend upon you realizing that "the only" is not identical to "only" or "only if" or "only when." The phrase "the only" (as in "the only way" and "the only people" and "the only time," etc.) is its own special thing that needs special attention.

The first way to look at "the only" is to recognize that while it does indicate a necessary condition, it is not next to the necessary condition in the sentence. The sufficient condition will come between the phrase and the condition that it refers to. To understand why this is the case, consider this statement: "The only people allowed in the Green Room are the celebrity guests and their entourages." Now ask yourself this - who are "the only people?" That would be the celebrity guests and their entourages. They are the ones that "the only people" refers to, so since "the only" is a necessary condition indicator, those people must be the necessary condition. That would be diagrammed this way:

Allowed in Green Room :arrow: Celeb Guests or Entourage

That's the way I always approach that phrase, by asking myself "what is the only way" or "who are the only ones," etc., and my answer to that question is my necessary condition.

But then there is this alternative approach, preferred by some folks (but not by me): treat "the only" as a sufficient condition indicator. It's special, an exception to the normal rule about "only." Whatever it is next to - whatever it introduces - is sufficient, and the other thing that comes later is necessary. In my example above, "the only people" is next to "allowed in the Green Room," so that must be the sufficient condition, and the people are necessary. Notice that this approach results in the exact same diagram?

Choose your approach, whichever one appeals to you, and stick with it, and you will never again have a problem with "the only" as you did here!
 uchong
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#81394
Thank you Adam. That is helpful!
 Reneasp1
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#97353
Can someone please explain to me why (E ) is incorrect?
 Robert Carroll
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#97399
Reneasp1,

As explained in the first post of this thread, answer choice (E) is a Mistaken Reversal. It doesn't do any good in this stimulus to introduce the Mistaken Reversal of the relationship already given, so that's definitely not an assumption necessary for the argument.

Robert Carroll
 Asal1998
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  • Joined: Jun 16, 2024
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#109024
Hello!

I understand why the answer is A because that's the only option that fills the logical gap of the stimuli, by connecting plays that are popular and plays that get played regularly.

However, I'm not able to get the answer using conditional reasoning. Can you please explain what I'm doing wrong?

Premise 1: The only plays that continue to be performed regularly over many decades and centuries are those that skillfully explore human nature
Premise 2: none of the plays written last year examine human nature in a particularly skillful way.
Conclusion: none will be popular several centuries from now.

Premise 1: PR --> SEHN (this seems correct based on the explanation in this form)
Premise 2: Play --> ~SEHN (this is where I get lost)
Conclusion: Play --> ~ Pop

PR -- plays that are performed regularly
SEHN -- skillfully explore human nature
Play -- plays written last year
Pop -- plays that are popular


thank you!!!!
 Robert Carroll
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#109615
Asal,

Your diagrams look good. Contrapose the first one:

SEHN :arrow: PR

That then connects with the second premise to make a chain:

Play :arrow: SEHN :arrow: PR

Answer choice A gives the following:

Pop :arrow: PR

Contrapose that:

PR :arrow: Pop

Now if that were added to the chain you already have, the entire thing would look like this:

Play :arrow: SEHN :arrow: PR :arrow: Pop

The conclusion of the argument is simply the endpoints of this chain.

Robert Carroll

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