If I see a question similar to this one on the test, I believe it would be a valid response for me to run the fade with the first person that I see immediately upon viewing that question. Let me know the general consensus.
@NicholasDylewski I assume you're talking about B, since it's the only answer that concerns what should be done instead of what shouldn't be done. B does not present the contrapositive. In conditional logic, it makes the mistaken assumption that negating the sufficient condition must then negate the necessary condition.
Structurally, the reasoning is identical to saying:
"If something is fluffy and cute, then it is a dog. Since this creature is neither fluffy nor cute, then it is not a dog."
The correct contrapositive in this case would be something like:
"If it is not wrong for to play a practical joke, then that practical joke BOTH shows no contempt for the target AND was not perpetrated under the jokester's belief that it would harm the target."
Notice how B reverses the sufficient and necessary conditions in that statement.
i wish the PSAa questions came before PSAr in the curriculum - i feel like the lessons for PSAa have helped me understand the logic required for the question type so much more
@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.
See this confused me at first too. but I think i get it now. we can do a contrapositive here, but we would get if you should do the practical joke, then it must not be contemptuous and you don't think it'd cause harm. so we know facts about the joke if you should do them, but, in this case, we have no idea what the sufficient conditions are for if you should do it. we have no conditional statement to provide reasoning for why you should, which is what he means.
from my understanding when negating a condition still allows for the meaning to be communicated accurately.
it is wrong to play a practical joke vs. it is unacceptable to play a practical joke.
the negation of wrong isn't right, it's not wrong. so i dont think you could contrapose something like that for a PSA question. the negation of unacceptable is just acceptable though, so i think you could contrapose it for this question type.
written horribly but hopefully you can understand what im getting at. seems to work for me
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
I feel like this explanation is misguiding people to assume that you can never contrapose PSA(r or a) question types, or at least that's what it sounds like. B is just wrong because it is still using the CAN make a practical joke as the necessary condition and the not contempt and not harm as sufficient conditions, if they were reversed and it was both, it would satisfy the contrapositive of changing or to "and". Maybe I'm overthinking it but it felt like JY was saying you can never contrapose a rule, haha.
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. ;)
I can take a stab. Let's us this example: if you get a good LSAT score, you will get a scholarship. The lawgic would be: good LSAT SCORE --> scholarship.
Finding the contrapositive would tell us this in lawgic: No scholarship ---> not a good LSAT score. This contrapositive is a valid conclusion, as all people who get a good LSAT score will always get a scholarship. So, if you did not get a scholarship, you could not have gotten a good LSAT score.
Confusing sufficiency and necessary conditions would be if you thought that all people who get scholarships have to have good LSAT scores. The original statement does not tell us Scholarship ---> LSAT score. There could be other ways to get a scholarship -- for example having great essays or having overcome personal struggle. We thus know that it is not necessary to have a good LSAT score to get a scholarship.
In the example from this video our stimulus provides two sufficient conditions:
shows contempt ---> should not play practical joke
believes significant harm could be inflicted --> should not play practical joke
You only need one of these sufficient conditions to trigger the principle. Just because one does not show contempt does not mean they should play a practical joke (to do so would be confusing a sufficient condition for a necessary one). For example, one could believe that significant harm would happen through their joke even if they don't show contempt, which would still trigger the rule stated in the stimulus. Confusing the necessary for the sufficient would be if you thought if one should not play a practical joke then they must show contempt and/or they must believe significant harm would be brought.
What we do know is that if you should play a practical joke than both of those sufficient conditions (shows contempt and believes significant harm could be inflicted) are not true. We know this through the contrapositives of both relationships:
should play practical joke ---> does not show contempt
should play practical joke ----> does not believe significant harm would be brought.
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.
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.
my issue with answer choice C, is that how are we sure that the person BELIEVES that it could bring them harm. Sure, playing the joke could bring harm, but does the person believe it could bring that harm?
I think it is because the answer choice (all of them, actually) are structured as quotes or thoughts by the person. If they are saying or thinking "this could harm you" then obviously they believe that to be true.
Contrast that to answer choice A, where they realize the potential for harm only with the benefit of hindsight. The implication there is that at the time of the action, they didn't believe that to be the case.
108 comments
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
we got em with this one ah question
If I see a question similar to this one on the test, I believe it would be a valid response for me to run the fade with the first person that I see immediately upon viewing that question. Let me know the general consensus.
holy crap, it's Jimmy McGill from the hit series Better Call Saul and Breaking Bad! If I find Harvey Specter in here, I'll eat a phone book.
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.
this question genuinely made my head hurt
me too iamgonnacrashout
C is getting Philosophical
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
Do we know if correct answer choices on PSAa questions will ever be the contrapositive?
Hi! Since posting this, have you ever encountered any correct ACs that were the contrapositive for PSAa questions?
Update: question 9 from pt 149 section 1 is a PSAr question in which the correct AC is the contrapositive!
Why cant an answer choice follow the contrapositive of the rule?
@NicholasDylewski my exact questio
@NicholasDylewski I assume you're talking about B, since it's the only answer that concerns what should be done instead of what shouldn't be done. B does not present the contrapositive. In conditional logic, it makes the mistaken assumption that negating the sufficient condition must then negate the necessary condition.
Structurally, the reasoning is identical to saying:
"If something is fluffy and cute, then it is a dog. Since this creature is neither fluffy nor cute, then it is not a dog."
The correct contrapositive in this case would be something like:
"If it is not wrong for to play a practical joke, then that practical joke BOTH shows no contempt for the target AND was not perpetrated under the jokester's belief that it would harm the target."
Notice how B reverses the sufficient and necessary conditions in that statement.
i wish the PSAa questions came before PSAr in the curriculum - i feel like the lessons for PSAa have helped me understand the logic required for the question type so much more
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.
@MacBean this makes so much more sense now thank you!
@MacBean THANK YOU!
We need a grammar lesson with this term "Prescriptive Conclusion" he keeps using in alot of videos. That would really help us.
the bait from A is crazy
#feedback So when can you contrapose??
See this confused me at first too. but I think i get it now. we can do a contrapositive here, but we would get if you should do the practical joke, then it must not be contemptuous and you don't think it'd cause harm. so we know facts about the joke if you should do them, but, in this case, we have no idea what the sufficient conditions are for if you should do it. we have no conditional statement to provide reasoning for why you should, which is what he means.
from my understanding when negating a condition still allows for the meaning to be communicated accurately.
it is wrong to play a practical joke vs. it is unacceptable to play a practical joke.
the negation of wrong isn't right, it's not wrong. so i dont think you could contrapose something like that for a PSA question. the negation of unacceptable is just acceptable though, so i think you could contrapose it for this question type.
written horribly but hopefully you can understand what im getting at. seems to work for me
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
I feel like this explanation is misguiding people to assume that you can never contrapose PSA(r or a) question types, or at least that's what it sounds like. B is just wrong because it is still using the CAN make a practical joke as the necessary condition and the not contempt and not harm as sufficient conditions, if they were reversed and it was both, it would satisfy the contrapositive of changing or to "and". Maybe I'm overthinking it but it felt like JY was saying you can never contrapose a rule, haha.
To me, B looks like the wrong way of contraposing.
If A, then B (A→B)
Contraposed: If NOT B, then NOT A (
B→A)If the rule set out in the stimulus was
If contempt OR harm then NOT joke ( C →
JH →J)But answer B has it written as (at least to me)
If NOT contempt or NOT harm, then joke (
C→JH→J)As an additional side, B also basically says "If it's not contemptuous and harmful (DeMorgan's), you can play the joke).
But we don't know the standards for playing a joke.
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. ;)
can you not create a contrapositive?
Can you clarify confusing sufficiency and necessary condition vs. finding the contrapositive of a conditional? #help
This also is confusing to me--I would appreciate clarification as well!
Also would appreciate further clarification on this! #help
I can take a stab. Let's us this example: if you get a good LSAT score, you will get a scholarship. The lawgic would be: good LSAT SCORE --> scholarship.
Finding the contrapositive would tell us this in lawgic: No scholarship ---> not a good LSAT score. This contrapositive is a valid conclusion, as all people who get a good LSAT score will always get a scholarship. So, if you did not get a scholarship, you could not have gotten a good LSAT score.
Confusing sufficiency and necessary conditions would be if you thought that all people who get scholarships have to have good LSAT scores. The original statement does not tell us Scholarship ---> LSAT score. There could be other ways to get a scholarship -- for example having great essays or having overcome personal struggle. We thus know that it is not necessary to have a good LSAT score to get a scholarship.
In the example from this video our stimulus provides two sufficient conditions:
shows contempt ---> should not play practical joke
believes significant harm could be inflicted --> should not play practical joke
You only need one of these sufficient conditions to trigger the principle. Just because one does not show contempt does not mean they should play a practical joke (to do so would be confusing a sufficient condition for a necessary one). For example, one could believe that significant harm would happen through their joke even if they don't show contempt, which would still trigger the rule stated in the stimulus. Confusing the necessary for the sufficient would be if you thought if one should not play a practical joke then they must show contempt and/or they must believe significant harm would be brought.
What we do know is that if you should play a practical joke than both of those sufficient conditions (shows contempt and believes significant harm could be inflicted) are not true. We know this through the contrapositives of both relationships:
should play practical joke ---> does not show contempt
should play practical joke ----> does not believe significant harm would be brought.
I eliminated A because it refers to harming "someone" which doesn't necessarily mean it's talking about the target of the joke.
This is a common pattern in wrong answers which I sometimes glaze over: "Should have realized" vs. "believed"
Other examples:
"occurred" vs. "believed"
Is there an earlier lesson that talks about prescription-to-judgment inferences?
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.
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"
my issue with answer choice C, is that how are we sure that the person BELIEVES that it could bring them harm. Sure, playing the joke could bring harm, but does the person believe it could bring that harm?
would like to hear any clarifications on this
I think it is because the answer choice (all of them, actually) are structured as quotes or thoughts by the person. If they are saying or thinking "this could harm you" then obviously they believe that to be true.
Contrast that to answer choice A, where they realize the potential for harm only with the benefit of hindsight. The implication there is that at the time of the action, they didn't believe that to be the case.