if this helps, the way I am thinking about this which one is being limited; The NECESSARY condition is always the one that limits and The SUFFICIENT condition is the thing being limited.
All we need to know is a basic subject or a symbol for it, and whether that concept starts out as a positive or negative. My example starts out with "Not" so if we choose this to negate and place in front then the subject would just be "rain" as opposed to if "cloudy" was chosen and it would be negated to not cloudy.
When you have a double negative happening it cancels out the negatives.
As an example you can think of two little siblings if Kid A is in trouble and says they didn't get in the cookie jar and Kid B tells the parent that they didn't "not not" get in the cookie jar in a snotty tone.
Kid B is saying they got into the cookie jar just using a double negative and being a pain. They could have totally thrown Kid A under the bus but they didn't, instead they chose to indirectly say what happened while burying it under extra fluff of double negations. In its own way the LSAT is doing the same by choosing the more convoluted manner of saying each contrapositive.
If the stimulus is hard then you can fall back onto the direct translation of the logical indicator to get the correct answer. Even if the information does not make immediate sense when reading it. The LSAT seems to intentionally try to throw people off by staying things in a way obscures the structure of the argument.
If this says that: Blackouts WILL occur UNLESS the heat wave abates.. Then how does it make sense to say: If the heat wave doesnt abate, then blackouts will occur?
Wouldnt it be: If the heatwave doesnt abate, then blackouts wont occur?
i find it easiest to just read the exception indicators as 'if not' instead of following the rule of choosing one, negating it, and making it sufficient
SO COnFUsing. I just think of it like. If theres two options for one thing, thats the necessary immediately off the bat. THe sufficient cant have more than one outcome. :)
I know that we are just starting to learn the "necessary and sufficient" concepts, but does anyone have tips on identifying what's "necessary" and what's "sufficient" without relying on indicator words? I feel like I have been doing okay with exercises because the indicator words are obvious, but I know the LSAT will make it tricky and omit them.
Is the blackout the superset and the heat wave not abating the subset? I understand it more clearly if I visualize the circles (subset → superset). Since the heave wave not abating isn't the only one of the things that could cause a blackout there are other possible sub sets that could fit within the superset of the blackout.
To put this in really simple layman's terms, you have to think about whether one thing can still happen without the other thing. So in this case, blackouts can still occur even without a heat wave. That is why the statement "if the heatwave abates, then blackouts will not occur" is not the correct choice. Blackouts can still very much happen without a heat wave, think man caused fire damaging the electrical grid, equipment failing, a tree falling on a power line, etc.
You might as well introduce the concept of a disjunction. for "unless". People who have a some understanding of logic will struggle because they want a "lawgic" rule to fully encompass what a sentence actually means.
I think the largest problem with this question is that it does not address the importance of 'will' in the argument. By changing 'will' to 'won't', it fundamentally makes the question wrong because blackouts have several means of occurring, whereas 'don't' does not necessarily mean they won't happen, but it rules out the possibility of a heatwave causing the problem.
I think the majority of this concern could have been avoided if you provided a flipped version of 'If the heatwave abates, then blackouts won't occur'.
TLDR: Regardless of how you flip it, the word 'will' implies that it is necessary for blackouts to occur if there is a heatwave, thus making it (heatwaves) your sufficient condition regardless of negation.
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118 comments
It will snow, unless the clouds are blue
Step 1) Unless is the conditional indicator
Step 2) Identify the 2 conditions
Condition 1: It will snow
Condition 2: Unless the clouds are blue
Step 3:
Condition 1: Snow
Condition 2: Blue
Translation rule
Step 1) Select 1 of the ideas
It will snow
Step 2) Negate the idea
It will not snow
/snow
Step 3) Make that the sufficient idea
/snow -> blue
It will not snow, unless the clouds are blue
Step 4) Take the contrapositive
/blue -> Snow
If the clouds are not blue, than it will snow
if this helps, the way I am thinking about this which one is being limited; The NECESSARY condition is always the one that limits and The SUFFICIENT condition is the thing being limited.
when you summarize the negate/sufficient rule, why do you drop the "take the contrapositive" rule #5? it makes it seem like its not required
Example:
It will not rain unless it is cloudy.
In this there are two concepts.
not rain --- group 3 indicator--- cloudy
Translation-rain then cloudy
Contrapositive- not cloudy then not rain
All we need to know is a basic subject or a symbol for it, and whether that concept starts out as a positive or negative. My example starts out with "Not" so if we choose this to negate and place in front then the subject would just be "rain" as opposed to if "cloudy" was chosen and it would be negated to not cloudy.
When you have a double negative happening it cancels out the negatives.
As an example you can think of two little siblings if Kid A is in trouble and says they didn't get in the cookie jar and Kid B tells the parent that they didn't "not not" get in the cookie jar in a snotty tone.
Kid B is saying they got into the cookie jar just using a double negative and being a pain. They could have totally thrown Kid A under the bus but they didn't, instead they chose to indirectly say what happened while burying it under extra fluff of double negations. In its own way the LSAT is doing the same by choosing the more convoluted manner of saying each contrapositive.
If the stimulus is hard then you can fall back onto the direct translation of the logical indicator to get the correct answer. Even if the information does not make immediate sense when reading it. The LSAT seems to intentionally try to throw people off by staying things in a way obscures the structure of the argument.
what types of problems does this apply to. Im learning all these concepts and it doesn't really seem to apply on most of the practice questions
This doesnt make sense to me...
If this says that: Blackouts WILL occur UNLESS the heat wave abates.. Then how does it make sense to say: If the heat wave doesnt abate, then blackouts will occur?
Wouldnt it be: If the heatwave doesnt abate, then blackouts wont occur?
I've found it useful to envision things like these as a double-arrow. Not sure if that's legit logically, but it's worked for me.
finally got it
HELP IM UNDERSTANDING
for some reason, no matter what i do i cannot figure out which is the necessary and which is sufficient.
does anyone have an easy to not mix up sufficient and necessary conditions. i keep mistaking them not matter what i do
i find it easiest to just read the exception indicators as 'if not' instead of following the rule of choosing one, negating it, and making it sufficient
SO COnFUsing. I just think of it like. If theres two options for one thing, thats the necessary immediately off the bat. THe sufficient cant have more than one outcome. :)
Blackouts will occur unless the heat wave abates.
If the heat wave doesn't abate, then blackouts will not occur.
If blackouts won't occur, then the heat wave abates.
They are all saying the same thing, right?
[This comment was deleted.]
I know that we are just starting to learn the "necessary and sufficient" concepts, but does anyone have tips on identifying what's "necessary" and what's "sufficient" without relying on indicator words? I feel like I have been doing okay with exercises because the indicator words are obvious, but I know the LSAT will make it tricky and omit them.
Is the blackout the superset and the heat wave not abating the subset? I understand it more clearly if I visualize the circles (subset → superset). Since the heave wave not abating isn't the only one of the things that could cause a blackout there are other possible sub sets that could fit within the superset of the blackout.
I started out getting it by vibe, then got more confused, and now mostly get it by understanding the actual logical relationship. Funny how that works
GOD BLESS ITS STARTING TO MAKE SENSE
To put this in really simple layman's terms, you have to think about whether one thing can still happen without the other thing. So in this case, blackouts can still occur even without a heat wave. That is why the statement "if the heatwave abates, then blackouts will not occur" is not the correct choice. Blackouts can still very much happen without a heat wave, think man caused fire damaging the electrical grid, equipment failing, a tree falling on a power line, etc.
You might as well introduce the concept of a disjunction. for "unless". People who have a some understanding of logic will struggle because they want a "lawgic" rule to fully encompass what a sentence actually means.
Group 1 (if, when, all, any, etc.) — what comes after is the sufficient condition.
Group 2 (only if, must, always, etc.) — what comes after is the necessary condition.
Group 3 (unless, until, without, or) — what comes after is negated, then becomes the sufficient condition.
There will be a blackout, unless the heatwave abates. This is saying that if the heatwave continues, there will be a blackout.
If the heat wave does not abate, then it will cause a blackout.
If no blackout occurs, then the heat wave must have abated. Otherwise, the heat wave would have caused a blackout.
If the heat wave abates, there are still other threats that could cause a blackout, such as unrelated equipment failure.
This is the moment that I understand what people mean when they say this is like learning a new language.
#feedback
I think the largest problem with this question is that it does not address the importance of 'will' in the argument. By changing 'will' to 'won't', it fundamentally makes the question wrong because blackouts have several means of occurring, whereas 'don't' does not necessarily mean they won't happen, but it rules out the possibility of a heatwave causing the problem.
I think the majority of this concern could have been avoided if you provided a flipped version of 'If the heatwave abates, then blackouts won't occur'.
TLDR: Regardless of how you flip it, the word 'will' implies that it is necessary for blackouts to occur if there is a heatwave, thus making it (heatwaves) your sufficient condition regardless of negation.