The way it is laid out in the arrow example of Super set Necessary subset. was initially confusing. But i parsed it like this. You have to be (necessary) in the USA if you are in New York that must be true 100 percent of the time. However being in New York means you are in the USA (sufficient) But you do NOT HAVE to be (necessary) in New York to be in the USA. Maybe this will help someone
Eating shrimp is sufficient to eat Seafood, but not necessary.
Since shrimp is a subset (belonging to the seafood group) you can eat shrimp which would be sufficient enough to eating A SEAFOOD. BUT it is not necessary to eat ALL foods of seafood.
You can eat from the specific (shrimp) which is a subset of seafood which is a general group, but it is not necessary.
Eating seafood is necessary to eat shrimp, but not sufficient.
If you are in the superset of seafood, that must mean it is necessary to eat shrimp. Shrimp is a specific item of seafood.
But it is not sufficient to just eat shrimp. If you eat seafood, it is not sufficient that you are eating shrimp. You don't have to eat shrimp, but it is necessary that you eat a seafood.
Another Example:
The city of Houston is sufficient to be in the USA, but not Necessary.
Living in the city of Houston is specific, sufficient, and JUST ENOUGH to be in the United States, BUT NOT NECESSARY.
You can live in any city and still be in the USA. It is not necessary to live in Houston, if you want to be in the United States you can live in NYC, LA, etc.
The country of USA is necessary to be in the city of Houston, but not sufficient.
Living in the USA is necessary if you want to live in the city of Houston but is not sufficient.
But it is not sufficient to just live in Houston. You can live in any city and be in the USA, as long as the city is located in the USA.
Subset → Superset Being in the small group is enough to be in the big group .If you work at OPA, you definitely work in D.C. politics
If you work at OPA, then you definitely work in D.C. politics — being in the small group is sufficient for being in the big group.
BUT…
You can work in D.C. politics without being in OPA (e.g., Cyrus, Mellie, Fitz when he was president).
So being in OPA is not necessary to be in the D.C. politics group.
Superset → Subset Being in the big group is required but not enough to be in the small group Olivia trusting you doesn’t automatically place you in OPA
To be in Olivia’s inner circle, you MUST be someone she trusts. So being in the big group (people she trusts) is necessary.
BUT…
Just because she trusts you doesn’t automatically put you in her inner circle. For example, she trusted Fitz, but he wasn’t in OPA’s inner circle.
So being in the big group is not sufficient to put you in the small group.
If you got this far, may God supply you with whatever you need to do well for this test!
so would an example be Birmingham (subset) and Alabama (superset). Birmingham is sufficient for living in Alabama, but not necessary. Living in Alabama is necessary to live in Birmingham.
Loved the way he explained this. Subset (NYC) membership is sufficient (Okay) for superset (USA) membership because you have to be in the USA to be NYC but it is not necessary because you can be the Grand Canyon and still be in the USA.
While
Superset (USA) membership is necessary (needed) for subset (NYC) membership because you have to be in the USA but not sufficient if its earth.
He explained it well— but I got confused a bit so I added more understanding.
A mammal subset is not dependent on cats— it’s Sufficient (S) as a stand alone. Whereas, Cats are dependent as a Necessary (N) needing mammals in order to stand.
A cat (subset) — is a (necessary) — mammal (superset).
A mammal (superset) — is Not (why? Bc, Sufficient) — a cat.
And we know this— because mammals are a larger extended category compared to cats— where as the only difference within cats are modifier (fat, colored, etc).
I had a hard time understanding this, but I continued through the lesson. Once you work with some real LSAT problems, come back to this video. It will click!!!
A tip to help anyone that is confused: Don't use the words "membership", "Sufficient", and "necessary." Instead just say something like this: Being a part of mammal set is not enough to be a part of cat set—but being a mama is needed to be a part of cat set. Or: You need to be a mammal or a part of mammal set to be in the cat club. Play around with the words.
All squares are a type of rectangle but not all rectangles are sqaures!
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150 comments
I've struggled with sufficiency for some reason, so wrote out a couple things that helped -
Being in subset is sufficient for membership in superset.
If in subset, guaranteed in superset.
If in subset, must be in superset.
If in subset, necessarily in superset.
Being in superset is not sufficient for membership in subset.
If in superset, not guaranteed to be in subset.
If in superset, could be in subset.
If in superset, not necessarily in subset.
Sufficiency is like - is this information sufficient for me to believe another thing.
Claim: Jane lives in New York. Is that sufficient for me to assume she lives in the US? Yes it is sufficient.
Claim: Jane lives in the US. Is that sufficient for me to assume she lives in New York? No, it is not sufficient.
Claiming Jane lives in New York so she must live in US is valid. Must be true.
Claiming Jane lives in US so she must live in New York is not valid. Could be true.
im slight confused .. someone please help me understand. this is what i broke it down into on my notes
if i am a cat then i am a mammal - sufficient
BUT
if i am a mammal, im not necessarily a cat. i can be a mammal without being a cat - necessary
like
if im in miami then im in florida - sufficient
BUT
if im in florida it doesnt necessarily mean that im in miami because i could be in orlando and still be in florida - neccesary
am i getting this right...??
Subset membership is enough for superset membership but not required. Superset membership is required for subset membership, but not enough.
The way it is laid out in the arrow example of Super set Necessary subset. was initially confusing. But i parsed it like this. You have to be (necessary) in the USA if you are in New York that must be true 100 percent of the time. However being in New York means you are in the USA (sufficient) But you do NOT HAVE to be (necessary) in New York to be in the USA. Maybe this will help someone
sufficiency (subset) vs necessity (superset)
Eating shrimp is sufficient to eat Seafood, but not necessary.
Since shrimp is a subset (belonging to the seafood group) you can eat shrimp which would be sufficient enough to eating A SEAFOOD. BUT it is not necessary to eat ALL foods of seafood.
You can eat from the specific (shrimp) which is a subset of seafood which is a general group, but it is not necessary.
Eating seafood is necessary to eat shrimp, but not sufficient.
If you are in the superset of seafood, that must mean it is necessary to eat shrimp. Shrimp is a specific item of seafood.
But it is not sufficient to just eat shrimp. If you eat seafood, it is not sufficient that you are eating shrimp. You don't have to eat shrimp, but it is necessary that you eat a seafood.
Another Example:
The city of Houston is sufficient to be in the USA, but not Necessary.
Living in the city of Houston is specific, sufficient, and JUST ENOUGH to be in the United States, BUT NOT NECESSARY.
You can live in any city and still be in the USA. It is not necessary to live in Houston, if you want to be in the United States you can live in NYC, LA, etc.
The country of USA is necessary to be in the city of Houston, but not sufficient.
Living in the USA is necessary if you want to live in the city of Houston but is not sufficient.
But it is not sufficient to just live in Houston. You can live in any city and be in the USA, as long as the city is located in the USA.
hey, so i don't get it lol
This example was confusing to me :( Thank you to people in the comments for additional examples and breakdowns!
Being in the United States is necessary to be in NYC, but not sufficient.
Being in NYC is sufficient to be in the United States, but not necessary.
Because dogs.
This is a fantastic sentence.
All cats (subset) are mammals (superset). So, mammal club's membership is necessary to be in the cat club.
But not all mammals are cats. So, cat club membership is sufficient, but not necessary, to be in the mammal club.
A cat must be a mammal. But a mammal may or may not be a cat.
Subset → Superset Being in the small group is enough to be in the big group .If you work at OPA, you definitely work in D.C. politics
If you work at OPA, then you definitely work in D.C. politics — being in the small group is sufficient for being in the big group.
BUT…
You can work in D.C. politics without being in OPA (e.g., Cyrus, Mellie, Fitz when he was president).
So being in OPA is not necessary to be in the D.C. politics group.
Superset → Subset Being in the big group is required but not enough to be in the small group Olivia trusting you doesn’t automatically place you in OPA
To be in Olivia’s inner circle, you MUST be someone she trusts. So being in the big group (people she trusts) is necessary.
BUT…
Just because she trusts you doesn’t automatically put you in her inner circle. For example, she trusted Fitz, but he wasn’t in OPA’s inner circle.
So being in the big group is not sufficient to put you in the small group.
If you got this far, may God supply you with whatever you need to do well for this test!
so would an example be Birmingham (subset) and Alabama (superset). Birmingham is sufficient for living in Alabama, but not necessary. Living in Alabama is necessary to live in Birmingham.
Loved the way he explained this. Subset (NYC) membership is sufficient (Okay) for superset (USA) membership because you have to be in the USA to be NYC but it is not necessary because you can be the Grand Canyon and still be in the USA.
While
Superset (USA) membership is necessary (needed) for subset (NYC) membership because you have to be in the USA but not sufficient if its earth.
google helped me on this one. i was getting too caught up in the language.
He explained it well— but I got confused a bit so I added more understanding.
A mammal subset is not dependent on cats— it’s Sufficient (S) as a stand alone. Whereas, Cats are dependent as a Necessary (N) needing mammals in order to stand.
A cat (subset) — is a (necessary) — mammal (superset).
A mammal (superset) — is Not (why? Bc, Sufficient) — a cat.
And we know this— because mammals are a larger extended category compared to cats— where as the only difference within cats are modifier (fat, colored, etc).
Hope this helped. This is from my notes.
can someone explain Superset membership is necessary for subset membership, but not sufficient. in terms of the cats?
I had a hard time understanding this, but I continued through the lesson. Once you work with some real LSAT problems, come back to this video. It will click!!!
I understand the logic, I just don't understand the WORDS (sufficient & necessary)
So say I'm Lubbock, Texas.
To be in Lubbock it is necessary that I am in Texas. To be in Texas it is necessary that I am in the USA.
Lubbock is a subset of Texas and USA is a superset to Texas.
It is sufficient if I live in Texas to be in Lubbock and sufficient to be in the USA if im in Texas?
I think I understand it but I’m not sure …
It is sufficient that basketball is a sport, but not necessary for the sport to be basketball????
A tip to help anyone that is confused: Don't use the words "membership", "Sufficient", and "necessary." Instead just say something like this: Being a part of mammal set is not enough to be a part of cat set—but being a mama is needed to be a part of cat set. Or: You need to be a mammal or a part of mammal set to be in the cat club. Play around with the words.
subset membership--->superset membership, in NYC--->in USA
ya'll get any of that?
hey so this makes no sense and it makes me want to die
All squares are a type of rectangle but not all rectangles are sqaures!