Being on earth is sufficient for being in the universe, but not necessary. Being in the universe is neccessary for being on earth but not sufficent. You can be on Mars or Pluto and still be part of the universe.
I feel like this is a good question to ask yourself that is substitutable. "If I'm a cat do I have to be a mammal?" Yes, being a mammal is necessary for being a cat, therefore mammal is the necessary condition in this relationship. This question is substitutable in that you can just ask yourself "If I'm x do I have to be Y?" If the answer is yes then Y is more than likely the necessary condition. Sorry if this has been mentioned but this helped me be able to understand the point enough to simply explain to other people. Also the question you ask yourself should be phrased in relation to the material in the question. I could say "if I'm in Syracuse then I'm in Indiana....I'm in Syracuse therefore I'm in Indiana" and it could be logical true but factually wrong and asking yourself "If I'm in Syracuse do I have to be in Indiana" would make you second guess but if that's what the stimulus says, I hope not, but you would go along with it. Hopefully what I just said is correct too.
Also from the way I'm understanding it (someone please correct me if I'm wrong), sufficiency is usually a guarantor but not necessary because it's a specific subset of a category? Is a good rule of thumb (when looking at these types of questions) to sniff out what the broader categories are to better relate sufficiency and necessity?
Preworkout is sufficient (guarantees) that it is a caffeinated drink.
Being a caffeinated drink is necessary (required) for it to be preworkout. But not the other way around. Saying something is a caffeinated drink isn't enough for you to infer that it's preworkout; it could be coffee, tea, Monster, etc.
Playing basketball is sufficient to be playing a sport (because basketball is a sport). However, playing basketball is not necessary to be playing a sport (could be playing another sport).
Playing a sport is necessary to be playing basketball (because basketball is a sport). However playing a sport is not sufficient to be playing basketball (could be playing another sport).
Being in Paris is sufficient to be in France, however being in France is not sufficient to be in Paris (could be in another city).
Being in France is necessary to be in Paris, however being in Paris is not necessary to be in France (could once again be in another city).
Another Ex:
A Honda is sufficient to be a car, however a car is not sufficient to be a Honda (other car brands exist).
A car is necessary to be a Honda, however a Honda is not necessary to be a car (other car brands exist).
Final Ex:
Lisa is at the grand crayon, therefore it is sufficient to conclude she is in USA. However, Lisa being in the USA would not be sufficient to conclude that she is at the grand canyon (could be elsewhere).
The USA is a necessary condition for Lisa to visit the Grand Canyon. However it is not necessary for Lisa to visit the Grand Canyon in order to be in the USA (could be elsewhere).
I feel like he needs to draw the diagram differently to create a better understanding. If you claim sufficiency for a subset, then the arrows need to point down. However, if you claim necessity for a superset, the arrow needs to go upwards. I feel like that may make better sense if trying to graph it on your own.
can someone tell me if this logic is right. To be in the grocery cart it must be a food. Dessert is a type of food so it is suffient to be put in the cart. However, to be in the cart it does not have to be dessert. But if there is dessert in the cart then it must be a food.
Earrings are sufficient to be jewelry, but not necessary (because jewelry could also be rings, necklaces, etc.). Jewelry is necessary to be earrings, but not sufficient (not all jewelry are earrings).
A teacher is sufficient for a career, but not necessary.
A career is necessary for a teacher.
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77 comments
superset: Universe
subset: earth
Being on earth is sufficient for being in the universe, but not necessary. Being in the universe is neccessary for being on earth but not sufficent. You can be on Mars or Pluto and still be part of the universe.
I feel like this is a good question to ask yourself that is substitutable. "If I'm a cat do I have to be a mammal?" Yes, being a mammal is necessary for being a cat, therefore mammal is the necessary condition in this relationship. This question is substitutable in that you can just ask yourself "If I'm x do I have to be Y?" If the answer is yes then Y is more than likely the necessary condition. Sorry if this has been mentioned but this helped me be able to understand the point enough to simply explain to other people. Also the question you ask yourself should be phrased in relation to the material in the question. I could say "if I'm in Syracuse then I'm in Indiana....I'm in Syracuse therefore I'm in Indiana" and it could be logical true but factually wrong and asking yourself "If I'm in Syracuse do I have to be in Indiana" would make you second guess but if that's what the stimulus says, I hope not, but you would go along with it. Hopefully what I just said is correct too.
Superset: Athlete
Subset: Olympian
being an athlete is necessary to be an Olympian
being an Olympian is sufficient to be an athlete, but not necessary.
Subset: Earth
Superset: Solar System
Being on Earth is sufficient for being in the Solar System, but not necessary.
You can be on any planet, like Mars, because it is not necessary to be JUST on Earth.
As long as you are on a planet, it is sufficient.
Being in the Solar System is necessary for being on planet Earth, but not sufficient.
In order to be on Earth, you must be in the Solar System.
Superset: Employee
Subset: janitor
Being a janitor is sufficient to being an employee
Being an employee is necessary to be a janitor
#feedback for the web managers - when you pause the videos the screen goes blank / white making it very difficult to take notes.
subset: toddler
superset: kids
being a toddler is sufficient for being a kid
being a kid is necessity for being a toddler
yes or no??
Now I'm lost.
Also from the way I'm understanding it (someone please correct me if I'm wrong), sufficiency is usually a guarantor but not necessary because it's a specific subset of a category? Is a good rule of thumb (when looking at these types of questions) to sniff out what the broader categories are to better relate sufficiency and necessity?
Subset: Preworkout
Superset: Caffeinated drinks
Preworkout is sufficient (guarantees) that it is a caffeinated drink.
Being a caffeinated drink is necessary (required) for it to be preworkout. But not the other way around. Saying something is a caffeinated drink isn't enough for you to infer that it's preworkout; it could be coffee, tea, Monster, etc.
Subset: Monday
Superset: Weekdays
Being Monday is sufficient for being a weekday (guarantees it).
Being a weekday is necessary for being a Monday (requirement — Monday can’t exist outside the weekday set).
Subset: Cookies
Superset: Desserts
Being a cookie is sufficient for being a dessert
Being a dessert is necessary to be a cookie
Subset (sufficient): ballerina
Superset (necessary): dancer
Being a ballerina is sufficient for being a dancer.
Being a dancer is necessary for being a ballerina.
Subset: Plant 🌱
Superset: Rose 🥀
Being a rose is sufficient for being a plant. (Being a rose is good enough to be a plant)
Being a plant is necessary for being a rose. (Being a plant isn’t an option for a rose)
subset: guitar
superset: instrument
being a guitar is sufficient to be an instrument
being an instrument is necessary to be a guitar
subset: television
superset: electronic
being a television is sufficient to be an electronic.
being an electronic is necessary to be a television.
subset: student at harvard
superset: student
Being a student is necessary to being a student at Harvard
But it is not necessary to be a student at harvard to be a student
Subset: basketball
Superset: sports
Playing basketball is sufficient to be playing a sport (because basketball is a sport). However, playing basketball is not necessary to be playing a sport (could be playing another sport).
Playing a sport is necessary to be playing basketball (because basketball is a sport). However playing a sport is not sufficient to be playing basketball (could be playing another sport).
Sufficiency and Necessity exist only in relation to eachother.
(subset) and (superset)
Subset: Paris
Superset: France
Being in Paris is sufficient to be in France, however being in France is not sufficient to be in Paris (could be in another city).
Being in France is necessary to be in Paris, however being in Paris is not necessary to be in France (could once again be in another city).
Another Ex:
A Honda is sufficient to be a car, however a car is not sufficient to be a Honda (other car brands exist).
A car is necessary to be a Honda, however a Honda is not necessary to be a car (other car brands exist).
Final Ex:
Lisa is at the grand crayon, therefore it is sufficient to conclude she is in USA. However, Lisa being in the USA would not be sufficient to conclude that she is at the grand canyon (could be elsewhere).
The USA is a necessary condition for Lisa to visit the Grand Canyon. However it is not necessary for Lisa to visit the Grand Canyon in order to be in the USA (could be elsewhere).
I feel like he needs to draw the diagram differently to create a better understanding. If you claim sufficiency for a subset, then the arrows need to point down. However, if you claim necessity for a superset, the arrow needs to go upwards. I feel like that may make better sense if trying to graph it on your own.
can someone tell me if this logic is right. To be in the grocery cart it must be a food. Dessert is a type of food so it is suffient to be put in the cart. However, to be in the cart it does not have to be dessert. But if there is dessert in the cart then it must be a food.
this is how i break it up in my mind
grocery cart- superset
food- subset of cart
dessert- subset of food
To be a fork is sufficient for cutlery. It is the not neccessary as there are other types of cutlery. To be cutlery is neccesary to be a fork.
Am I correct:
subset: earrings
superset: jewelry
Earrings are sufficient to be jewelry, but not necessary (because jewelry could also be rings, necklaces, etc.). Jewelry is necessary to be earrings, but not sufficient (not all jewelry are earrings).
Am I right?
Subset: teacher
Superset: career
A teacher is sufficient for a career, but not necessary.
A career is necessary for a teacher.