#20 - One should not play a practical joke on someone

[Administrator]

Complete Question Explanation

Parallel Reasoning—PR, SN. The correct answer choice is (C)

In this stimulus, we have a relatively simple conditional statement presented as a principle. One should not play a practical joke on another person if either 1) it shows contempt for that person, or 2) if one believes it might cause that person significant harm. We can diagram the relationship as follows:

• Sufficient Necessary
  
  Shows contempt for that person
  Or Should not play practical joke on that person.
  Believes it will cause
  significant harm to that person

Therefore, if either of the above conditions are true, then you should not play the practical joke.
An additional difficulty with this question is comes with the question stem. The language of the stem, “most helps to justify,” initially appears like a Strengthen question. However, it is important to be aware of the relationship between the stimulus and the answer choices. In a Strengthen question, the question stem would direct us to use the answer choices to help the stimulus. In this question stem, it directs us to move from the stimulus to the answer choices, and use the principle in the stimulus to find the answer choice that fits. This relationship is what we would expect in a Parallel Reasoning question, and therefore, we want to find the answer choice that matches the reasoning in the stimulus.

Answer choice (A): In this example, the joke was not contemptuous. Further, the answer choice states that the individual should have known it would cause harm. This is different than believing it would cause harm. In fact, by stating that he or she should have known that it would cause harm, it implies that the individual did not believe that it would cause harm. Therefore, since this choice does not implicate either sufficient condition, we cannot determine that the necessary would automatically follow.

Answer choice (B): This answer choice is a Mistaken Negation. It states that since it does not show contempt, and the speaker does not think it will cause harm, then it would not be wrong to play the practical joke. The answer choice just negates the conditional relationship, but does not reverse the terms.

Answer choice (C): This is the correct answer choice. In this answer choice, the joke does not show contempt. However, the speaker reasonably believes that the joke will cause harm to the potential target of the joke. Therefore, the speaker concludes that it would be wrong to play the joke. This is the exact parallel of our stimulus, where the sufficient condition, that the speaker reasonably believes the joke would cause harm to the target, leads to the necessary condition, that the speaker should not perform the joke.


Answer choice (D): The sufficient conditions in the stimulus are limited to contempt for or harm to the intended target of the joke; this answer choice expands the stimulus to contempt for anyone, or harm to someone. Since it does not match the conditional relationship in the stimulus, this answer choice is not correct.

Answer choice (E): We do not know if the speaker should have reasonably believed that the joke would cause harm. Further, just like in answer choice (D), this answer choice impermissibly attempts to expand the conditional relationship to harm to anyone as opposed to harm to the target of the joke.

[melissa27]

For this question my diagram was

Shows contempt or believe harm --> not play joke

play joke--> not show contempt and not believe harm.

with this I was able to eliminate A but had a hard time trying to decide between the rest of the answer choices. Could you explain how b, d, and e are wrong?

[Steve Stein]

You got the diagrams right--if a practical joke shows contempt for a person or if you believe that it will seriously harm that person, you shouldn't play that joke.

B is a mistaken negation of your second diagram.

D lacks contempt and lacks harm, so there is no basis to conclude that it would have been wrong.

E says that, in retrospect, someone was harmed--that doesn't mean that the person playing the joke believed (beforehand) that it would seriously harm the victim.

Let me know whether that clears that one up--thanks,

~Steve

[testtakernce]

Hey guys,

I am having the hardest time understanding principle questions. How they work. What you can conclude..etc.


Ok so I just the October 2011. I encountered the following principle question from Section 3. #20 "One should not play a practical joke on someone...."

I diagrammed it as the following:

show contempt for that person or believes it might bring harm ---> ~play practical joke

I chose C but was a little unclear on why answer choice B was wrong.

1) Is answer choice C correct because you can conclude that it would be wrong to play the practical joke because one of the sufficient conditions was met (cause significant harm), therefore we can conclude that the necessary could occur.

2) Does this mean that if we take the contrapositive of the original statement and get:

play practical joke------> ~show contempt for that person + ~cause significant harm to that person

Can we conclude the necessary in this case as well? In other words would the statement: It wouldn't be wrong if Michael played the practical joke on you, so he must have realized that the joke wouldn't show contempt for you nor would it cause you significant harm" be a valid?

I concluded the necessary of the contrapositive statement "so he must have realized that the joke.."

Is bring this up because I saw a similar situation when doing practice problems from the Feb 2000 LSAT section 2 #16 "To act responsibly in one's professional capacity"

The question sets up the diagram: Act R-----> info accurate + complete

The correct answer concludes that Toril did not act responsibly because she was not complete. I figured this answer was correct because it is the contrapositive of the original statement:

~accurate or ~complete-----> ~ Act R

3) Was the answer correct because it concluded the necessary by showing that the sufficient isn't fufilled?
But now I'm confused because in the LR Bible it says that you cannot conclude that the necessary has not occurred because the sufficient hasn't occurred. Here the sufficient hasn't occurred, can we then conclude that the necessary doesn't occur as well? That seems like mistaken reversal...

I'm so confused. Any help would be greatly appreciated!

[Nikki Siclunov]

Hi testtakernce,

Thanks for your question. Principle questions are not exactly a separate question type, but rather an "overlay" generally added to MBT, Strengthen, and Justify questions: the Principle indicator broadens the scope of the question, and typically involves the deduction (or application) of conditional reasoning statements. This is because principles are generally thought of as rules or other normative statements that specify what actions (or judgments) are applicable if certain sufficient conditions are met. Let's take a look at the two questions you are asking about:

Your diagram of the principle contained in the stimulus is correct (where T stands for the target of one's joke):

Show contempt for T or Believe joke would harm T wrong to play the joke

The stem asks us to figure out which of five judgments can best be justified by the principle contained in the stimulus. Close reading is key.

Answer choice (C) is indeed correct, because it satisfies the second one of two conditions (belief that the joke would cause harm to the person targeted by the joke), either one of which would be sufficient to justify the conclusion that the joke should not be played.

Your interpretation of the contrapositive is correct; however, an answer choice that applies the principle in its contrapositive would posit playing the practical joke as an a priori given (i.e. a premise), and the qualities defining the joke - as a conclusion. Your hypothetical example demonstrates such an application. However, this is not how the answers here are presented: in all of them, whether or not a joke should be played is conclusionary idea, not a premise. The contrapositive, therefore, plays no role in determining the correct answer choice.

Answer choice (B) is not analogous to your example, because in it the statement "it was not wrong to play the joke" functions as a conclusion, not a premise. Such a conclusion cannot be deduced from the principle contained in the stimulus. This is because satisfying either sufficient condition amounts to a prohibition, not a mandate, to play the practical joke. Indeed, even if neither sufficient condition is met, it may still be wrong to play the joke (to conclude otherwise would be a Mistaken Negation of the principle).

Regarding Question 16 from February 2000, the principle in it can be diagrammed as follows:

Act responsibly Effort to verify info is accurate + complete

Your analysis of answer choice (C) is correct: Toril failed to meet the necessary condition for acting responsibly, so the conclusion that he did not act responsibly is justified.

Notice, however, the difference between the two principles you are asking about: in the first one, the judgment ("it would be wrong to play a practical joke") functions as a necessary condition, mandated by the occurrence of either one of two sufficient conditions. We can accordingly conclude when it's wrong to play a practical joke, but cannot conclude when it is not wrong to play it. By contrast, in the February 2000 question, the judgment ("acting responsibly") functions as a sufficient condition, requiring the satisfaction of a necessary condition. Thus, we cannot use the February 2000 principle to draw a conclusion that someone acted responsibly (that would be a Mistaken Reversal), but we absolutely can use it to conclude when they did NOT act that way (using the contrapositive).

Hope this helps a bit! Let me know.

Thanks.

[avengingangel]

Thanks for all the really helpful explanations! I had the same approach / chose the correct answer, however, in working through it all, some larger questions about general approaches came up for me (as it seems to happen with so many of these questions . I think really just having someone confirm my thought process / explanations here would really help the lesson/info sink in, to make sure I am on the right track:

Similar to one thing I think testtakerrnce was getting at, I was a bit confused by the conditional relationship in the stimulus, since, as Nikki perfectly put it, "satisfying either sufficient condition amounts to a prohibition, not a mandate." (Which is unusual to see in the LSAT, right or no??) So I was thrown off when I did the contrapositive of my diagram of the stimulus:

should do it contempt and harm.

The question in my book I scribbled down was: "It seems like the argument/stimulus/principle is concerned with when you should not play a practical joke on someone, but the contrapositive seems to be giving me information about when one should play a practical joke???" (as I've just shown you)... which totally freaked me out, as it goes against everything I've learned thus far about conditional relationships & contrapositives.

BUT THEN, I thought about it some more (mainly thought about why B, the answer I originally chose, was wrong), and then wrote / realized: "Contempt and harm are not sufficient reasons to not play a joke, but they are necessary. Just because you don't "have" them does not mean you should play the joke, but it is necessary to not have either things if you were to play the joke and it be "OK," according to the principle in the stimulus." I also realized why I was so confused before: I incorrectly thought "the argument/stimulus/principle is concerned with when you should not play a practical joke on someone" because I was interpreting my diagram as if "should not" was the sufficient condition, when in fact it was the necessary (which is what I correctly wrote down, but I guess I couldn't process that in my head because I wasn't used to seeing that)...

SO -- I should have (correctly) thought instead that the the argument/stimulus/principle is concerned with when a joke doesn't show contempt for someone and when you think a joke will bring significant harm to that person...

Whew! I hope that all makes sense. I would really appreciate any one's thoughts on this for clarity / confirmation / learning purposes! Thanks !!!

[Adam Tyson]

That's a lot to digest, Angel, but I think you have it! To determine the sufficient and necessary conditions here one need only look to the all-important word "if" That indicator word introduces the sufficient conditions here, which are causing harm and showing contempt. The prohibition (you should not play the joke) is therefore necessary.

When thinking about the contrapositive, it might be helpful to think about the negation of "should not" as being more holistic than mechanical. The negation of "should not" is "should not, but is that the same as "should"? We could be mechanical about it, and then we would read the result as "IF you should play a joke on someone, then that joke would not show contempt or cause them harm", and that would be absolutely valid. The problem is, it's not quite right. Instead, use the language that Nikki used of "wrong" vs. "not wrong", or your own choice of "okay" vs "not okay". That you should not do it is the same as saying that it is wrong, or that it is not okay. The negation would be "if it isn't wrong" or "if it is okay". Those aren't compelling anything, just allowing it. The prohibition is lifted. That's the sufficient condition of the contrapositive, the elimination of the prohibition.

You're good to go on this one. Nice job!

[avengingangel]

Great, thanks, I really appreciate it. The fact that the necessary condition is a prohibition of something really threw me for a doozy here! But, again, this is a great lesson to learn / remember, for when I am faced with a similar situation. Thanks for taking the time to address the approach!

[mankariousc]

Hello!

While I understand how C is the correct answer I don't understand why B is a Mistaken Negation. I eliminated B because it said "could harm anyone" and the stimulus says that it should be specific to the person the joke is being played on. I had a hard time applying the diagram to each answer choice--even the correct one. Could you help me with this?

Thank you!

[Emily Haney-Caron]

Hi mankariousc,

Applying diagrams in this kind of question definitely takes practice! Here's how we would diagram B:
Shows contempt for that person
AND Ok to play practical joke on that person
Believes it will cause
significant harm to that person

This diagram negates all the terms, and changes or to and, which is what you do when you take the contrapositive. BUT, it fails to switch the terms onto the other sides of the arrow. That's what a mistaken negation is: it leaves everything on the same sides of the arrow but negates each term. Do you see how this one is different from the diagram Administrator answer, above?

This is the kind of thing that gets easier with practice, and this is why it is so important to practice diagramming AND taking the contrapositive, so you can spot when something isn't quite right!