The example that I think about when thinking about how sufficient-necessary relationships work is the following: If I'm in New York, that's sufficient to know I'm in the U.S., but being in the U.S. does not mean I'm in New York. Being in New York is sufficient to know I'm in the U.S., and being in the U.S. is necessary to be in New York.
This analogy has really helped me understand sufficiency vs. necessity. As my kitchen is in my house, being in my kitchen is sufficient to be in my house (sufficiency). And being in my house is necessary to be in my kitchen (necessity).
However, this is how you may confuse necessity with sufficiency. Being in my kitchen is not necessary to be in my house, since you can hang out in the dining room or living room, and still be in my house.
On the other hand, being in my house is not sufficient for being in my kitchen, since you can be anywhere else in my house instead of the kitchen (e.g especially if I barred you from entering the kitchen).
This was helpful! In this video he used how Oxygen is necessary for water BUT is not sufficient because it also needs Hydrogen.
He also used a causation example for sufficient. For example, a power outage caused computer crashes. The power outage is sufficient for causing the computer crash-- in that, it does not need any thing further to cause the computer crash. In comparison, it is not necessary that there is a power outage for the computers to crash-- they can exist seperate from each other.
I really struggled with this concept so here are some phrases that have seemed to help:
Sufficient: "is enough by itself." Being human is a sufficient condition for being a mammal. I would say "being human is enough by itself to be a mammal (it needs nothing else)"
Necessary: "must be." Hydrogen in necessary in water. I would say "hydrogen must be in water."
air is necessary for humans to live—without it, a person would die.
However, it is not sufficient because it cannot, by itself maintain human life as there are other factors required for survival, like water and food.
Similarly, if an advertised job requires that the candidate holds a Master's degree,
the qualification is necessary but will not guarantee they get the job, and is, therefore, not sufficient.
On the other hand, jumping from a plane at 20,000 feet without a parachute is sufficient for death;
however, there are many other ways one might die and it is, therefore, not necessary.
Likewise, being a mother is sufficient but not necessary for being female in the same way that a room being square is sufficient but not necessary for it having four walls (it could be rectangular).
Think of it like a concert or an amusement park. Superset is like the general admission ticket and subset is like the VIP access or fast pass. You still get into the concert or amusement park by having general admission to enter even if you don't have VIP access to do certain things or get on rides faster. So having the VIP access/fastpass isn't necessary to be in the concert/park but you can have the exclusiveness and still be considered someone attending the venue.
Defining sets as sufficient typically starts at the subset and looks outwards. Per the example, cat-set is sufficient for mammal-set.
On the other hand, when you define sets as necessary, you start at the superset and looks inward. Per the example, mammal-set is necessary for cat-set.
This is how the terms sufficient and necessary are able to accurately describe the relationship between sets.
It took me a REALLY long time to think this through:
Being in Los Angeles (subset) is sufficient to know you're in California (superset), but being in Los Angeles (subset) is not necessary for knowing you're in California (superset). You don't necessarily need to know that you're in Los Angeles in order to know you're in California; you could be in San Diego, Sacramento, or San Jose. As long as you are in California, it's not necessary to know WHERE EXACTLY you are in California, in order to know you're already in California.
Let's say the border of California was equipped with a high-tech alarm system that would blare sirens and absolutely let you know that you walked into the ocean/Oregon/Nevada/Arizona. And let's say you were blind-folded, dropped into the center of California, and told to walk around randomly in any direction for 3 hours. At the end of those 3 hours, you stop walking, and you know for a fact that the alarm never went off during your 3 hour walk. You know you never left California because the sirens never blared. So you have to KNOW you're in California, even though you have no clue what part of the state you're in. Are you north? Are you south? Doesn't matter. That's what it means by: "subset membership is not necessary for superset membership". Knowing you're in Los Angeles is not necessary for knowing you're in California.
Came back to this lesson after studying/drilling for 4 months and plateauing largely due to challenges with necessity/sufficiency issues on more advanced questions.
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).
Honestly, I had a decent understanding of sufficiency and necessity before this video and this just confused the heck out of me. Am I the only one? Maybe too many moving parts.
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
I know I'm thinking about this backwards because this doesn't fit JY's logic but perhaps you can help me understand. If we've established that Garfield is a cat, isn't it then NECESSARY for that cat to be a mammal? How is being a cat sufficient to being a mammal? This is me thinking bottoms-up instead of top-down because that's how my mind works -- I go straight to the dot and try to rationalize/interpret.
You asked "How is being a cat sufficient to being a mammal?". Im going to replace the word sufficient with necessary.
How is being a cat necessary to being a mammal? Its not right? I can be a human or a dog and be a mammal. Being a cat is not necessary to being a mammal. But its sufficient. If you are a cat, then its sufficient to say youre a mammal. So think more generally like that question
as long as we're able to make the relationships and understand them, know what is true and what isn't necessarily-true, then point A to point B by any route is fine right?
@yesterdayseeker I agree, the circles are a bit confusing. Understanding the arrow and the different sides sufficiency and necessity are on the arrow helps. Also, learning how to chain together claims in deeper passages helps.
I came back to this at the end of the "Conditional and Set Logic" portion because I was still a little confused on the definitions. But reading it again with the information I have now, the "Let's Review" section makes way more sense. If it's a little confusing now, keep pushing, it might make more sense for you towards the end.
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The example that I think about when thinking about how sufficient-necessary relationships work is the following: If I'm in New York, that's sufficient to know I'm in the U.S., but being in the U.S. does not mean I'm in New York. Being in New York is sufficient to know I'm in the U.S., and being in the U.S. is necessary to be in New York.
This is a fantastic example, thank you!
this is example helped me understand it sooo much better!!! thank you!!
Much easier to remember honestly. Thank you!
This analogy has really helped me understand sufficiency vs. necessity. As my kitchen is in my house, being in my kitchen is sufficient to be in my house (sufficiency). And being in my house is necessary to be in my kitchen (necessity).
However, this is how you may confuse necessity with sufficiency. Being in my kitchen is not necessary to be in my house, since you can hang out in the dining room or living room, and still be in my house.
On the other hand, being in my house is not sufficient for being in my kitchen, since you can be anywhere else in my house instead of the kitchen (e.g especially if I barred you from entering the kitchen).
I hope that helps y'all!
This was helpful!
This was really great, thank you!
If you have trouble understanding this lesson, watch this YouTube video; it helped me immensely.
https://youtu.be/3R1W3jhtCY4?si=e9fw9SyKBrdiWAJs
This was helpful! In this video he used how Oxygen is necessary for water BUT is not sufficient because it also needs Hydrogen.
He also used a causation example for sufficient. For example, a power outage caused computer crashes. The power outage is sufficient for causing the computer crash-- in that, it does not need any thing further to cause the computer crash. In comparison, it is not necessary that there is a power outage for the computers to crash-- they can exist seperate from each other.
I really struggled with this concept so here are some phrases that have seemed to help:
Sufficient: "is enough by itself." Being human is a sufficient condition for being a mammal. I would say "being human is enough by itself to be a mammal (it needs nothing else)"
Necessary: "must be." Hydrogen in necessary in water. I would say "hydrogen must be in water."
Let me know if I interpretted this correctly!
Super Helpful! Thank you
best video! thank you!!
hey so this makes no sense and it makes me want to die
This is something that helped me to understand:
For example,
air is necessary for humans to live—without it, a person would die.
However, it is not sufficient because it cannot, by itself maintain human life as there are other factors required for survival, like water and food.
Similarly, if an advertised job requires that the candidate holds a Master's degree,
the qualification is necessary but will not guarantee they get the job, and is, therefore, not sufficient.
On the other hand, jumping from a plane at 20,000 feet without a parachute is sufficient for death;
however, there are many other ways one might die and it is, therefore, not necessary.
Likewise, being a mother is sufficient but not necessary for being female in the same way that a room being square is sufficient but not necessary for it having four walls (it could be rectangular).
Source article: https://www.qualitativecriminology.com/pub/v5i2p1/release/1
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.
@gurbytown wow this is a great example, thank you so much for sharing it!
@gurbytown Thanks for sharing this! :) having a second example helped with making sense of it.
@gurbytown amazing example, thank you for sharing it!
@gurbytown Excellent example, I wrote this in my notes. Thank you stranger
Think of it like a concert or an amusement park. Superset is like the general admission ticket and subset is like the VIP access or fast pass. You still get into the concert or amusement park by having general admission to enter even if you don't have VIP access to do certain things or get on rides faster. So having the VIP access/fastpass isn't necessary to be in the concert/park but you can have the exclusiveness and still be considered someone attending the venue.
You are the best!
If A is a subset of B, then being in A is sufficient to imply you are in B.
It is not necessary to be in A to be in B because B may include other members outside of A.
Being in B is necessary in order to be in A, because every member of A lies within B
@LaurenJ24 Good explanation, thank you! :)
@LaurenJ24 UGH Thank you!!! Your comment helped me understand this better. I feel like the video overcomplicated it in trying to make it so simple.
EX. My house (sufficiency) is in Canada (necessity)
It is NECESSARY for me to be in Canada if I am in my house
It is SUFFICIENT for me to be in my house to be in Canada
It is impossible to be in my house without being in Canada
It is possible I am in Canada without being in my house
Do I have it right?
I think of it this way:
necessary=means MUST
sufficient= means (it is) ENOUGH.
Defining sets as sufficient typically starts at the subset and looks outwards. Per the example, cat-set is sufficient for mammal-set.
On the other hand, when you define sets as necessary, you start at the superset and looks inward. Per the example, mammal-set is necessary for cat-set.
This is how the terms sufficient and necessary are able to accurately describe the relationship between sets.
kept hearing katseye when he said cats set lol
It took me a REALLY long time to think this through:
Being in Los Angeles (subset) is sufficient to know you're in California (superset), but being in Los Angeles (subset) is not necessary for knowing you're in California (superset). You don't necessarily need to know that you're in Los Angeles in order to know you're in California; you could be in San Diego, Sacramento, or San Jose. As long as you are in California, it's not necessary to know WHERE EXACTLY you are in California, in order to know you're already in California.
Let's say the border of California was equipped with a high-tech alarm system that would blare sirens and absolutely let you know that you walked into the ocean/Oregon/Nevada/Arizona. And let's say you were blind-folded, dropped into the center of California, and told to walk around randomly in any direction for 3 hours. At the end of those 3 hours, you stop walking, and you know for a fact that the alarm never went off during your 3 hour walk. You know you never left California because the sirens never blared. So you have to KNOW you're in California, even though you have no clue what part of the state you're in. Are you north? Are you south? Doesn't matter. That's what it means by: "subset membership is not necessary for superset membership". Knowing you're in Los Angeles is not necessary for knowing you're in California.
Came back to this lesson after studying/drilling for 4 months and plateauing largely due to challenges with necessity/sufficiency issues on more advanced questions.
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.
@M1ckeymina this really helped me, thank you!
sooo im not confused lol but im not fully grasping it either. may have to circle back to this one
first time commenting. just have to say i'm beyond confused lol hoping it'll get clearer as I go on
@BrittanyJohnson Good luck, my friend, you got this!! you have the full force of all 7sage users supporting you 🙂↕️
I had to stop watching the explanation for this because it was just making me more confused when Id already grasped this from the earlier 30 min video
Honestly, I had a decent understanding of sufficiency and necessity before this video and this just confused the heck out of me. Am I the only one? Maybe too many moving parts.
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
So you CAN be a cat to be allowed in the mammal superset, but you HAVE to be a mammal to be allowed in the cat subset.
I know I'm thinking about this backwards because this doesn't fit JY's logic but perhaps you can help me understand. If we've established that Garfield is a cat, isn't it then NECESSARY for that cat to be a mammal? How is being a cat sufficient to being a mammal? This is me thinking bottoms-up instead of top-down because that's how my mind works -- I go straight to the dot and try to rationalize/interpret.
That's a great way of putting it!
Thank you fbotello91
You asked "How is being a cat sufficient to being a mammal?". Im going to replace the word sufficient with necessary.
How is being a cat necessary to being a mammal? Its not right? I can be a human or a dog and be a mammal. Being a cat is not necessary to being a mammal. But its sufficient. If you are a cat, then its sufficient to say youre a mammal. So think more generally like that question
too many sets and circles for me...
as long as we're able to make the relationships and understand them, know what is true and what isn't necessarily-true, then point A to point B by any route is fine right?
@yesterdayseeker I agree, the circles are a bit confusing. Understanding the arrow and the different sides sufficiency and necessity are on the arrow helps. Also, learning how to chain together claims in deeper passages helps.
this is not necessarily on the topic of s v n but the way that JY talks is so perfect for my ADHD brain i cant explain why but it helps so much LMAO
I came back to this at the end of the "Conditional and Set Logic" portion because I was still a little confused on the definitions. But reading it again with the information I have now, the "Let's Review" section makes way more sense. If it's a little confusing now, keep pushing, it might make more sense for you towards the end.
Being in Jack's bedroom is sufficient to be in Jack's house.
→ Not necessary as you can be in the kitchen and still be in Jack's house.
Being in Jack's house is necessary to be in his bedroom.
→ Not sufficient (aka necessary) to be in Jack's house to be in his bedroom.
Hope this helps :) Let's get that 170+