Love the little aside on the prescriptive "should". From my perspective, it's useful to think about should vs ought. Should, strictly understood, is subjective guidance defeasible for a good reason. Ought, strictly understood, is an objective authority giving a moral imperative (that can only be defeated with a superior moral imperative). But they overlap. Especially in modern usage, should can be used to mean ought. If should is being used in a principle, it could mean guidance (you should bring an umbrella), or it could mean it's a moral imperative (you shouldn't hit people), and you're going to have to look elsewhere for the clues as to which one is meant.
@JesseMcCarthy You can take the contrapositive which would be " should play joke -> /contempt and /believe it would cause harm " but that would not allow us to conclude that a joke should be played because the "should be" condition is sufficient and on the left side of the arrow.
shows contempt or believes harm --> /play practical joke
basically if shows c or believes h than do not play practical joke
contrapositive =
if play practical joke --> /show contempt and /believe harm
basically if you play practical joke then we know it does not show contempt and one does not believe harm.
AC B. is wrong because the original argument and the contrapositive DOES NOT assert when it would be wrong for one to play a joke. We just know what makes one not be able to play a practical joke and if one does do it what it should not have. AC. B. states it would not be wrong for me to play it but we do not know when it would be wrong.
woah this one was kind of hard. but once i went back and realized it said "to that person" and not "to anyone/someone" all the other answer choices fell apart.
Although I got it right, I'm curious when do we know a conclusion is unreachable? If it because this is an "or" statement? Why doesn't the contrapositive work in this circumstance?
@rjon27 update: i found the answer from a tutor on the discussion board for the question itself. Basically, still take the contrapositive but make sure to note if an answer choice is confirming the sufficient conditions (left side of the arrow) or the necessary conditions (right side of the arrow). B says that the necessary conditions are met but that doesn't mean the joke can be played. Hope this helps!
Tutor Answer:
Contrapositives are ALWAYS valid to use in answering any type of question. For this question, you started with a correct diagram of the stimulus:
Shows contempt OR believes it will bring significant harm -> /ok to play practical joke
The contrapositive of this is:
ok to play practical joke -> /show contempt AND /believe it will bring significant harm
Answer choice B shows the necessary conditions are satisfied. But if the necessary conditions for X are satisfied, that DOES NOT mean we can infer X. This is what 7Sage calls the "oldest trick in the book"—confusing necessary and sufficient conditions. You can read more about this common mistake here in our Argument Flaw Cheat Sheet: https://7sage.com/lessons/logical-reasoning/flaw-or-descriptive-weakening-questions/argument-flaw-cheat-sheet
Or you can apply the Jackass Negation: One should always play a practical joke on someone, especially if it shows contempt and/or could bring significant harm to that person. ;)
For B to be correct it would have to have the following structure: Since it would not be wrong for me to play the practical joke, it must be that the joke would show no contempt for the person it is played on and that I have no reason to think it would bring significant harm to anyone.
I don't understand how you couldn't take the contrapositive to make answer choice B work. Contempt -/-> PJ and believing harm -/-> PJ...therefore it makes sense to work backwards as well, with the opposite being true. Could someone explain?
@Tryingmybest Ideally with PSAa questions you want to find the argument that most closely matches the principle in its stated form, not a variation of it (ie contrapositive). There may be other reasons why one shouldn't play a practical joke other than the 2 stated that we don't know. This argument is basically saying that because the sufficient condition isn't met, the necessary condition can't be true, which is a logical fallacy. Additionally, as a rule I think prescriptive conclusions can't be contraposed the way other condition reasoning can be as the reasons that you shouldn't do something may totally differ from why you should do something, as opposed to being contrapositives.
Contrapositive: Joke ---> /Significant harm or /Contempt
B validates the necessary conditions in the contrapositive argument BUT remember, when we validate the necessary condition, that says nothing about the sufficient condition.
In other words: I can say the joke won't cause significant harm and it doesn't show contempt (necessary validated), but that doesn't mean I can draw a conclusion on whether or not I should say the joke (sufficient).
It's only when we reject (negate) the necessary can we then work back and negate the sufficient condition.
I was unsure between B and C because I fell for the contrapositive trap in B. B) says that the joke isn't believed to cause harm and would not show contempt for the target. That means that the rule we are given, which requires that one of these two sufficient conditions be met, is not triggered. In other words, B) does not lead to the conclusion that the joke should not be played. But does that mean that the joke should be played? No. Aren't there other reasons why it might be wrong to play a joke? We are given 2 conditions (harm and contempt) but there could be others. That's why the conclusion in B), that it would not be wrong to play the joke, is not a reachable conclusion from the rule we're given.
@MitulChowdhury No. The only contrapositive that can be taken is:
if it is NOT the case that one should not play a practical joke -> it would not cause harm to the target, and it would not cause that person harm.
As you can see, this is not the same thing as saying that you SHOULD play the joke. And even if it did say that, it is still the succificient condition, not the necessary.
Reasoning on why B is incorrect is somewhat questionable because why are we putting = between wouldn't be wrong and would be right? Because wouldn't be wrong also could mean neutral. A gray area exists.
he's not saying you can't contrapose, he's saying that no set of facts that the answer choices can provide us can ever deliver us to a conclusion that says you can play a practical joke.
There's a difference between having the necessary condition say "could play a practical joke" (which btw, in this question, is confusing suff. and nec. conditions and will always be logically incorrect) and the sufficient condition saying "could play a practical joke (which is the contrapositive of the argument).
You are forgetting that there are 2 triggers that would pull the conclusion, when they refer to anyone - yes it could also include "you" (the target), but its not enough to make the trigger happen. However, the 2nd half when discussing that the belief that it would harm someone, that significantly triggers as its the only answer out of the others to actual state that harm could happen to "you" (the target) and NOT anyone randomly. We need it to happen to you, thats why its wrong the play the joke. Not just anyone. Does that make sense? Lmk if that makes sense, that's how I got the question right.
Why is it not D? Did not understand from the explanation/video. Is it because it says anyone/someone instead of being specific about the target of the joke?
I also had eliminated D because I thought the stimulus has the sufficient condition that the joke "shows"contempt,whereas Answer Choice D says that "I did think that it would show"contempt. ie, it qualifies the contempt condition as a belief.
The stimulus only qualifies the harm condition with belief.
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86 comments
Love the little aside on the prescriptive "should". From my perspective, it's useful to think about should vs ought. Should, strictly understood, is subjective guidance defeasible for a good reason. Ought, strictly understood, is an objective authority giving a moral imperative (that can only be defeated with a superior moral imperative). But they overlap. Especially in modern usage, should can be used to mean ought. If should is being used in a principle, it could mean guidance (you should bring an umbrella), or it could mean it's a moral imperative (you shouldn't hit people), and you're going to have to look elsewhere for the clues as to which one is meant.
Can you not do contrapositive with De Morgan's Law?
@JesseMcCarthy You can take the contrapositive which would be " should play joke -> /contempt and /believe it would cause harm " but that would not allow us to conclude that a joke should be played because the "should be" condition is sufficient and on the left side of the arrow.
Arguement =
shows contempt or believes harm --> /play practical joke
basically if shows c or believes h than do not play practical joke
contrapositive =
if play practical joke --> /show contempt and /believe harm
basically if you play practical joke then we know it does not show contempt and one does not believe harm.
AC B. is wrong because the original argument and the contrapositive DOES NOT assert when it would be wrong for one to play a joke. We just know what makes one not be able to play a practical joke and if one does do it what it should not have. AC. B. states it would not be wrong for me to play it but we do not know when it would be wrong.
can you not create a contrapositive?
I get why C is the "most" correct but why would it be enough if it only covers one condition? and not the other -showing contempt- condition
@MelanieGonzalez The stim says "or."
@MelanieGonzalez since it says or only one could be sufficient for it to be triggered
woah this one was kind of hard. but once i went back and realized it said "to that person" and not "to anyone/someone" all the other answer choices fell apart.
Although I got it right, I'm curious when do we know a conclusion is unreachable? If it because this is an "or" statement? Why doesn't the contrapositive work in this circumstance?
@rjon27 update: i found the answer from a tutor on the discussion board for the question itself. Basically, still take the contrapositive but make sure to note if an answer choice is confirming the sufficient conditions (left side of the arrow) or the necessary conditions (right side of the arrow). B says that the necessary conditions are met but that doesn't mean the joke can be played. Hope this helps!
Tutor Answer:
Contrapositives are ALWAYS valid to use in answering any type of question. For this question, you started with a correct diagram of the stimulus:
Shows contempt OR believes it will bring significant harm -> /ok to play practical joke
The contrapositive of this is:
ok to play practical joke -> /show contempt AND /believe it will bring significant harm
Answer choice B shows the necessary conditions are satisfied. But if the necessary conditions for X are satisfied, that DOES NOT mean we can infer X. This is what 7Sage calls the "oldest trick in the book"—confusing necessary and sufficient conditions. You can read more about this common mistake here in our Argument Flaw Cheat Sheet: https://7sage.com/lessons/logical-reasoning/flaw-or-descriptive-weakening-questions/argument-flaw-cheat-sheet
Is there an earlier lesson that talks about prescription-to-judgment inferences?
we got em with this one ah question
Or you can apply the Jackass Negation: One should always play a practical joke on someone, especially if it shows contempt and/or could bring significant harm to that person. ;)
For B to be correct it would have to have the following structure: Since it would not be wrong for me to play the practical joke, it must be that the joke would show no contempt for the person it is played on and that I have no reason to think it would bring significant harm to anyone.
please stop hiding parts of the answer choices, i get you are trying to help but its messing with my brain.
We need a grammar lesson with this term "Prescriptive Conclusion" he keeps using in alot of videos. That would really help us.
I don't understand how you couldn't take the contrapositive to make answer choice B work. Contempt -/-> PJ and believing harm -/-> PJ...therefore it makes sense to work backwards as well, with the opposite being true. Could someone explain?
@Tryingmybest Ideally with PSAa questions you want to find the argument that most closely matches the principle in its stated form, not a variation of it (ie contrapositive). There may be other reasons why one shouldn't play a practical joke other than the 2 stated that we don't know. This argument is basically saying that because the sufficient condition isn't met, the necessary condition can't be true, which is a logical fallacy. Additionally, as a rule I think prescriptive conclusions can't be contraposed the way other condition reasoning can be as the reasons that you shouldn't do something may totally differ from why you should do something, as opposed to being contrapositives.
@Tryingmybest Another way to look at B is:
Significant harm and Contempt ---> /Joke
Contrapositive: Joke ---> /Significant harm or /Contempt
B validates the necessary conditions in the contrapositive argument BUT remember, when we validate the necessary condition, that says nothing about the sufficient condition.
In other words: I can say the joke won't cause significant harm and it doesn't show contempt (necessary validated), but that doesn't mean I can draw a conclusion on whether or not I should say the joke (sufficient).
It's only when we reject (negate) the necessary can we then work back and negate the sufficient condition.
what exactly does prescriptive language mean?
@SoniaKulkarni whether or not one *should do something. A descriptive statement is "its wrong to do x"
prescription, "one should not do x"
I was unsure between B and C because I fell for the contrapositive trap in B. B) says that the joke isn't believed to cause harm and would not show contempt for the target. That means that the rule we are given, which requires that one of these two sufficient conditions be met, is not triggered. In other words, B) does not lead to the conclusion that the joke should not be played. But does that mean that the joke should be played? No. Aren't there other reasons why it might be wrong to play a joke? We are given 2 conditions (harm and contempt) but there could be others. That's why the conclusion in B), that it would not be wrong to play the joke, is not a reachable conclusion from the rule we're given.
isn't B a contrapositive of the Rule in the question?
@MitulChowdhury No. The only contrapositive that can be taken is:
if it is NOT the case that one should not play a practical joke -> it would not cause harm to the target, and it would not cause that person harm.
As you can see, this is not the same thing as saying that you SHOULD play the joke. And even if it did say that, it is still the succificient condition, not the necessary.
Little key I made for myself:
PSA (LR Q#8) All Types: Prescriptive vs. Morally Descriptive Language
When/ When not to conflate the two is very tricky!
Often, wrong answer choices will use morally descriptive language in place of prescriptive
Seems correct, but is actually a trap answer
When to translate prescriptive to morally descriptive:
When stimulus makes prescriptions based on moral judgements
Ex. Do not prank disabled individuals
Here, answers that are morally descriptive could be correct
When NOT to translate prescriptive to morally descriptive:
When stimulus has nothing to do with morality at all
Ex. Do not forget to brush your teeth
Here, answers that are morally descriptive COULD NOT be correct
Brushing/not brushing arouses no moral judgements
Reasoning on why B is incorrect is somewhat questionable because why are we putting = between wouldn't be wrong and would be right? Because wouldn't be wrong also could mean neutral. A gray area exists.
the bait from A is crazy
Me when I’m literally saying the same shit over and over again
@inadsiwel You'll never convince me this shit is actually different man nobody gaf about these differences
#feedback. I'm confused about why you can't contrapose here.
Is this not correct?
could play a practical joke → /contempt and /b(significant harm)
he's not saying you can't contrapose, he's saying that no set of facts that the answer choices can provide us can ever deliver us to a conclusion that says you can play a practical joke.
There's a difference between having the necessary condition say "could play a practical joke" (which btw, in this question, is confusing suff. and nec. conditions and will always be logically incorrect) and the sufficient condition saying "could play a practical joke (which is the contrapositive of the argument).
C says contempt for anyone, how is it right b/c it isnt saying that particular person...??
You are forgetting that there are 2 triggers that would pull the conclusion, when they refer to anyone - yes it could also include "you" (the target), but its not enough to make the trigger happen. However, the 2nd half when discussing that the belief that it would harm someone, that significantly triggers as its the only answer out of the others to actual state that harm could happen to "you" (the target) and NOT anyone randomly. We need it to happen to you, thats why its wrong the play the joke. Not just anyone. Does that make sense? Lmk if that makes sense, that's how I got the question right.
I think its bc "you" would be included in "anyone"
Why is it not D? Did not understand from the explanation/video. Is it because it says anyone/someone instead of being specific about the target of the joke?
Because it says I thought it would show contempt for someone, when it should be show contempt for that person
I also had eliminated D because I thought the stimulus has the sufficient condition that the joke "shows" contempt, whereas Answer Choice D says that "I did think that it would show" contempt. ie, it qualifies the contempt condition as a belief.
The stimulus only qualifies the harm condition with belief.
If I see a similar question to this on the exam, I'll crash out, cry, and skip it because ain't nobody got time for that.