I think this question lends itself nicely to the subset, superset circles.
I imagine a big circle labeled "blackouts will occur"
Inside of that circle is a smaller circle labeled "heat wave does not abate," but that is not the only subset. For example, even if the heat wave abates, blackouts may occur because the power grid failed, or an earthquake, or something else. These would be other subsets of the "blackouts will occur" superset.
So, while the heat wave refusing to abate guarantees that blackouts will occur, the heat wave abating does not guarantee that blackouts will not occur, because a blackout could be caused by one of those other things.
this is how I solved this question, please let me know if I'm wrong because I got the confused sufficient for necessary right but my Lawgic was off.
My lawgic was BO->/HWA HWA->/BO
in earlier lesson it said if you see "unless" turn it into an "if not" statement.
Orignal: Blackouts will occur unless the heat wave abates
'IF NOT' : (suffi.) if the heat wave doesn't abate, then Blackouts will occur (Nece).
Lawgic: /HWB -> BO. /BO -> HWB
(half way through writing this I realized why my Lawgic was off...I confused sufficient for necessary conditions BRUHHH!! )
Question: which claims confused Suffi. for Necess. ? #2 is wrong b/c it flips our "if not" statement. also #1 matches the "If not" statement so it can't be that.
1) if the heat wave doesn't abate, then blackouts will occur
2) if the heat wave abate, then Blackout will not occur
this trick might not work with every "Unless" question but its still a good tool.
I dont understand when to know to take the contrapositive. When I tried the question myself I chose /HWA as the sufficient already, and thus did not need to take the contrapositive. How would I know to do that or take the contrapositive?
@taylorstryker You don't necessarily need to take the contrapositive right away. I usually start by diagramming the statement in its original form and then keep the contrapositive in mind as an equivalent version.
Whether you end up using the original conditional or the contrapositive depends on what the stimulus or answer choices give you. If an answer choice triggers the sufficient condition from your original diagram, use the original. If it gives you the negation of the necessary condition, the contrapositive may be more useful.
For example, if you have:
/BO --> HWA
the contrapositive is:
/HWA --> BO
Both statements are logically equivalent. So if an answer choice tells you heat waves do not abate, you would want to know that triggers blackouts occur (as given by the contrapositive). If it tells you blackouts do not occur, the original conditional is prob more helpful.
The main thing is not to think of the contrapositive as a separate rule that must be applied. It's just the same relationship expressed from the opposite direction. And sometimes that version will line up better with the information you're given.
Is taking the contrapositive a final necessary step to getting the correct answer? or can we translate back into English after negating one of the ideas and making it the sufficient?
@noaroxborough A contrapositive is something that is always true; it's another idea that's implied by a conditional. We don't always need to draw it out; but we do always need to understand it and recognize it.
"If A, then B."
We want to get to a point where we don't need to draw out "If Not B, then Not A" in order to understand that that follows from "If A, then B."
"Unless X, there is no Y."
That means "If Not X, then No Y" and "If Y, then X"
We want to get to a point where we don't need to draw out both of those ideas. Those statements mean the same thing and if we think of the statement as "If Not X, then No Y," we want to recognize it also means "If Y, then X" whether we draw it out or not.
It's like the idea of "X is taller than Y." Doesn't that also mean "Y is shorter than X"? Of course -- ideally we don't need to write anything out to see that. It's simply part of the meaning of "X is taller than Y"; it also means "Y is shorter than X."
i could be totally off base, but unless = "if not" was mentioned earlier right? so "blackouts will occur if not the heat wave abates" (disgusting but helpful to see) is the actual statement here. The sentence then becomes "If the heat wave does not abate, then blackouts will occur"
This threw me for a bit of a loop, but understanding wise i'm seeinng the part after the "unless" as the necessay condition while the part before is sufficient
when writing it down in lawgic, key part is unless = negate and herre negate the sufficient to get to necessary
@anamat I do too prefer whatever phrase that comes after the Group 3 indicators become the necessary condition, and the rest phrase becomes sufficient and you need to negate it. Instead of picking the idea then negating it.
@ShauneJa'CoreyPayne I was waiting to respond until I made another one, I made a set for quantifiers. I also made a folder that I will most likely add more sets to as I go. I'm taking my time to fully digest what I'm learning so it's taking longer but I want to make more as soon as I get through chunks of material lol here's the folder! https://quizlet.com/user/ehoffmanwallace/folders/lsat-7sage-flashcards
@TrinityLynn Yeah for sure, so cannot is a group 4 conditional indicator so it most likely will not appear in a statement. Let's use the example: "I will go to the park unless it rains" . Therefore my statement translated into lawgic would be.
/Going to the park --> Rains contrapositive /rains ---> going to the park. Translated back: If it rains, then I'm not going to the park. If it doesn't rain, then I'm going to the park. I hope this helps!
Why is it okay for the order of the argument to be flipped from A-->B to B-->A (at minute 4)? I thought that wasn't allowed unless we're taking the contrapositive.
Guys I gotchu. I figured it out. Basically every time we flip the contrapositive it worked for both claims before but now for Group 3, once you flip them, one of the flips won't be logical. When you get your translated sentences figure out which one makes sense.
"Blackouts will occur unless the heat wave abates"
We did the whole translation and now we have...
"If the heat wave doesn't abate, then blackouts will occur"
"If the heat wave abates, then blackouts will not occur"
Its basically an extra step of thinking which one makes the more sense. Like literally just think.... blackouts might still happen if a heat wave goes down. There are so many situations for a blackout, a measly heat wave going away doesn't guarantee that blackouts will not occur. For the others both translations worked and for this one only one of the translations works. I THINK.
(You can downvote me if I'm wrong I won't take it personally lol)
"John won't eat buffalo chicken cheese fries unless there's a mountain of guacamole on top"
Two Ideas: John won't eat his buffalo chicken cheese fries + there's a mountain of guacamole on top
Make first idea JWF (John won't fries)
Second idea MG (mountain guacamole)
Make one of them a negation (doesn't matter which) so then:
/MG > JWF
or
MG > /JWF
back to English:
If there is no mountain of guacamole on top, John won't eat his buffalo chicken cheese fries.
If there is mountain of guacamole on top, John will eat his buffalo chicken cheese fries.
Now think, which one matches the first statement. Remember our original sentence was "John won't eat buffalo chicken cheese fries unless there's a mountain of guacamole on top". Now which left side is more sufficient for the right side?
Winner: The second one. It's the exact same sentence! Read both aloud its pretty noticeable. The first one is not correct because it doesn't match the claim, it says something else. Plus- what if John was in a fries-eating contest worth a million dollars and all he had to do was eat his favorite fries without guacamole? Highly unlikely but it leaves the possibility where he WOULD eat fries without guacamole. Now I'm hungry for fries
@Super_Cookie I'm having a hard time understanding your example. Isn't the guac necessary for him to eat his fries but not sufficient? Your statement is saying that if his fries do not have guac he will not eat them. But that doesn't mean that if they DO have guac he WILL eat them (What if he's allergic to another ingredient, or it looks spoiled, etc.)
It is easy enough to understand that if the heat wave doesn't lessen, then blackouts will occur. What I cannot understand is if blackouts don't occur, then the heat wave lessens. Why is the heat wave lessening dependent on blackouts not occurring?
Example #1: “Blackouts will occur unless the heat waves abates.”
Translation Step 1: Identify the conditional indicator: The word “unless” is our identifiable conditional indicator.
Step 2: Identify the two main concepts (or groups, categories, events, or ideas): Blackouts will occur(first concept) and the other unless the heat waves abate (second concept).
Step 3: Assign Symbols to the main concepts: /BO → HWA → IF THE HEAT WAVE DOESN'T ABATE --> BLACK OUT OCCURS.
Step 4: Apply the translation rule LAWGIC: /BO → HWA
CONTRAPOSITIVE: /(HWA) → BO
Translating back to english: “If the heat wave doesn’t abate, then blackouts will occur.”
188 comments
I think this question lends itself nicely to the subset, superset circles.
I imagine a big circle labeled "blackouts will occur"
Inside of that circle is a smaller circle labeled "heat wave does not abate," but that is not the only subset. For example, even if the heat wave abates, blackouts may occur because the power grid failed, or an earthquake, or something else. These would be other subsets of the "blackouts will occur" superset.
So, while the heat wave refusing to abate guarantees that blackouts will occur, the heat wave abating does not guarantee that blackouts will not occur, because a blackout could be caused by one of those other things.
i get this but i also dont? like lol
this is how I solved this question, please let me know if I'm wrong because I got the confused sufficient for necessary right but my Lawgic was off.
My lawgic was BO->/HWA HWA->/BO
in earlier lesson it said if you see "unless" turn it into an "if not" statement.
Orignal: Blackouts will occur unless the heat wave abates
'IF NOT' : (suffi.) if the heat wave doesn't abate, then Blackouts will occur (Nece).
Lawgic: /HWB -> BO. /BO -> HWB
(half way through writing this I realized why my Lawgic was off...I confused sufficient for necessary conditions BRUHHH!! )
Question: which claims confused Suffi. for Necess. ? #2 is wrong b/c it flips our "if not" statement. also #1 matches the "If not" statement so it can't be that.
1) if the heat wave doesn't abate, then blackouts will occur
2) if the heat wave abate, then Blackout will not occur
this trick might not work with every "Unless" question but its still a good tool.
@YattaT I think your original lawgic is correct, why do you think you confused sufficiency for necessity?
I dont understand when to know to take the contrapositive. When I tried the question myself I chose /HWA as the sufficient already, and thus did not need to take the contrapositive. How would I know to do that or take the contrapositive?
@taylorstryker You don't necessarily need to take the contrapositive right away. I usually start by diagramming the statement in its original form and then keep the contrapositive in mind as an equivalent version.
Whether you end up using the original conditional or the contrapositive depends on what the stimulus or answer choices give you. If an answer choice triggers the sufficient condition from your original diagram, use the original. If it gives you the negation of the necessary condition, the contrapositive may be more useful.
For example, if you have:
/BO --> HWA
the contrapositive is:
/HWA --> BO
Both statements are logically equivalent. So if an answer choice tells you heat waves do not abate, you would want to know that triggers blackouts occur (as given by the contrapositive). If it tells you blackouts do not occur, the original conditional is prob more helpful.
The main thing is not to think of the contrapositive as a separate rule that must be applied. It's just the same relationship expressed from the opposite direction. And sometimes that version will line up better with the information you're given.
@taylorstryker So with this set of conditional indicators (like unless) I think hes saying the rule is simply you must negate.
Very confused but I won't give up
@petvma which part are you confused about?
Is taking the contrapositive a final necessary step to getting the correct answer? or can we translate back into English after negating one of the ideas and making it the sufficient?
@noaroxborough A contrapositive is something that is always true; it's another idea that's implied by a conditional. We don't always need to draw it out; but we do always need to understand it and recognize it.
"If A, then B."
We want to get to a point where we don't need to draw out "If Not B, then Not A" in order to understand that that follows from "If A, then B."
"Unless X, there is no Y."
That means "If Not X, then No Y" and "If Y, then X"
We want to get to a point where we don't need to draw out both of those ideas. Those statements mean the same thing and if we think of the statement as "If Not X, then No Y," we want to recognize it also means "If Y, then X" whether we draw it out or not.
It's like the idea of "X is taller than Y." Doesn't that also mean "Y is shorter than X"? Of course -- ideally we don't need to write anything out to see that. It's simply part of the meaning of "X is taller than Y"; it also means "Y is shorter than X."
This is the sweetets lesson I have found on this site ever. The fact that I can pick any part of the clause and make the SC, on volition.
I cannot convey how happy this is making me RN.
Can the word "unless" be treated like the word "without" in this case?
@GregErickson97 Unless, until, and without logically mean the same thing, yes.
i could be totally off base, but unless = "if not" was mentioned earlier right? so "blackouts will occur if not the heat wave abates" (disgusting but helpful to see) is the actual statement here. The sentence then becomes "If the heat wave does not abate, then blackouts will occur"
@CScheresky Yes! Wish they pulled this earlier rule into this lesson as well instead of a new rule
man this is just giving me mind mush bro
This threw me for a bit of a loop, but understanding wise i'm seeinng the part after the "unless" as the necessay condition while the part before is sufficient
when writing it down in lawgic, key part is unless = negate and herre negate the sufficient to get to necessary
a occurs unless b occurs
/a -> b
/b -> a
@anamat I do too prefer whatever phrase that comes after the Group 3 indicators become the necessary condition, and the rest phrase becomes sufficient and you need to negate it. Instead of picking the idea then negating it.
oh yes. I get my revenge on the ice and blizzard question finally. I have been fighting to understand it for a day now.
I feel like it doesn't confuse sufficiency for necessity, more you forgot that unless means to negate.
idk if that's right lmk lol!
@Catpop Forgetting that unless means to negate is the mistake that causes one to confuse sufficiency for necessity, I think
I would also sum it up by saying, only focus on the sole claim presented. Do not extrapolate meaning that is not explicitly stated.
I'm surprised you didn't use "Unless someone like you cares a whole awful lot, nothing is going to get better."
What happens when both clauses are negative (or we want to put in the sufficient part the negative clause)? For example
"Blackouts won't occur unless the heat wave doesn't abates."
Easy: it works like math. Negative + Negative = Positive, Positive + Negative = Negative.
Blackouts occur - Heat wave doesn't abate
Heat wave abates - Blackouts won't occur
Wow, you simplified this diagramming concept so easily for me! I was struggling with this for a while, thank you so much!!!!
I made flash cards to help memorize group 1-4 conditional indicators, thought I’d share in case it would be helpful to anyone else. I’m redoing this course after getting through most of it and taking the lsat and not doing as well as I hoped. Looking back I realize how important it is to know these. https://quizlet.com/1153975729/lsat-7sage-conditional-indicators-to-share-flash-cards/?i=71yhg9&x=1jqY
@Elideebeep Do you have anymore Quizlets?
@ShauneJa'CoreyPayne I was waiting to respond until I made another one, I made a set for quantifiers. I also made a folder that I will most likely add more sets to as I go. I'm taking my time to fully digest what I'm learning so it's taking longer but I want to make more as soon as I get through chunks of material lol here's the folder! https://quizlet.com/user/ehoffmanwallace/folders/lsat-7sage-flashcards
can someone explain using a different indicator
for example
"I cannot have fun without wine"
I tried to create my own statement and my brain is doing crazy things
@TrinityLynn Yeah for sure, so cannot is a group 4 conditional indicator so it most likely will not appear in a statement. Let's use the example: "I will go to the park unless it rains" . Therefore my statement translated into lawgic would be.
/Going to the park --> Rains contrapositive /rains ---> going to the park. Translated back: If it rains, then I'm not going to the park. If it doesn't rain, then I'm going to the park. I hope this helps!
Why is it okay for the order of the argument to be flipped from A-->B to B-->A (at minute 4)? I thought that wasn't allowed unless we're taking the contrapositive.
@EliBelly Are you referring to "/(heat wave abate) --> blackouts" and "/blackouts --> heat wave abate"? That looks like the contrapositive to me.
Guys I gotchu. I figured it out. Basically every time we flip the contrapositive it worked for both claims before but now for Group 3, once you flip them, one of the flips won't be logical. When you get your translated sentences figure out which one makes sense.
"Blackouts will occur unless the heat wave abates"
We did the whole translation and now we have...
"If the heat wave doesn't abate, then blackouts will occur"
"If the heat wave abates, then blackouts will not occur"
Its basically an extra step of thinking which one makes the more sense. Like literally just think.... blackouts might still happen if a heat wave goes down. There are so many situations for a blackout, a measly heat wave going away doesn't guarantee that blackouts will not occur. For the others both translations worked and for this one only one of the translations works. I THINK.
(You can downvote me if I'm wrong I won't take it personally lol)
@Super_Cookie Lemme try an example:
"John won't eat buffalo chicken cheese fries unless there's a mountain of guacamole on top"
Two Ideas: John won't eat his buffalo chicken cheese fries + there's a mountain of guacamole on top
Make first idea JWF (John won't fries)
Second idea MG (mountain guacamole)
Make one of them a negation (doesn't matter which) so then:
/MG > JWF
or
MG > /JWF
back to English:
If there is no mountain of guacamole on top, John won't eat his buffalo chicken cheese fries.
If there is mountain of guacamole on top, John will eat his buffalo chicken cheese fries.
Now think, which one matches the first statement. Remember our original sentence was "John won't eat buffalo chicken cheese fries unless there's a mountain of guacamole on top". Now which left side is more sufficient for the right side?
Winner: The second one. It's the exact same sentence! Read both aloud its pretty noticeable. The first one is not correct because it doesn't match the claim, it says something else. Plus- what if John was in a fries-eating contest worth a million dollars and all he had to do was eat his favorite fries without guacamole? Highly unlikely but it leaves the possibility where he WOULD eat fries without guacamole. Now I'm hungry for fries
@Super_Cookie I'm having a hard time understanding your example. Isn't the guac necessary for him to eat his fries but not sufficient? Your statement is saying that if his fries do not have guac he will not eat them. But that doesn't mean that if they DO have guac he WILL eat them (What if he's allergic to another ingredient, or it looks spoiled, etc.)
@Super_Cookie "Blackouts will occur unless the heat wave abates"
This does mean "If the heat wave does NOT abate --> blackouts will occur"
But the contrapositive still works:
"If blackouts do NOT occur --> then the heave wave DID abate"
This does not mean, however, that if the heat wave abates, blackouts won't occur. They can still occur for other reasons, even if the heat wave stops.
It is easy enough to understand that if the heat wave doesn't lessen, then blackouts will occur. What I cannot understand is if blackouts don't occur, then the heat wave lessens. Why is the heat wave lessening dependent on blackouts not occurring?
does it mean that if blackouts don't occur, it's BECAUSE the heat wave lessened?
I wish they would provide examples of how the LSAT tests this Negate sufficient..
Example #1: “Blackouts will occur unless the heat waves abates.”
Translation Step 1: Identify the conditional indicator: The word “unless” is our identifiable conditional indicator.
Step 2: Identify the two main concepts (or groups, categories, events, or ideas): Blackouts will occur(first concept) and the other unless the heat waves abate (second concept).
Step 3: Assign Symbols to the main concepts: /BO → HWA → IF THE HEAT WAVE DOESN'T ABATE --> BLACK OUT OCCURS.
Step 4: Apply the translation rule LAWGIC: /BO → HWA
CONTRAPOSITIVE: /(HWA) → BO
Translating back to english: “If the heat wave doesn’t abate, then blackouts will occur.”
oh dear my brain cannot wrap around this