@purplesunshine007 its so funny because youre the only other person ive ever seen use this form. i worked w a tutor once and i was like oh its like a math equation like they cancel each other out and he was like ... wtf are you talking about ?? I dont have a math brain by any means but these kinds of arguments reminded me of cancelling out two-sided equations lol
@bellaens18 I’m a philosophy graduate and that’s how we were talked to validate arguments in our logic class. In the back of the book was a list of rules like that one.
I think I struggle with the distinction between VALID arguments and TRUE arguments. If the Superset of "Ninjas" includes a subset of "Turtles", which includes "Donatello" then the argument is valid that donatello is a ninja, but it is not true that all turtles are ninjas. For the the argument to be both valid and true the subset would have to be TMNT.
@HealthLaw@28 I do believe so, yes! It seems as if formal arguments say that a member of a smaller group (subset) are always a member of a larger group (superset). Then, it plugs in an example into this smaller group to create sufficiency for membership into this larger group.
For example, "I have a cat. All cats are cute. Therefore, my cat is cute." In this example, cats (the member in question) are a subset of things that can fit into the "cute" superset label; many more things can be cute, and cats are just one of them. Saying, "I have a dog. All dogs are cute. Therefore, my dog is cute," would provide an example of another statement that expands the umbrella of "cute" things. In both examples, membership in the subset - dogs/cats - is sufficient for membership in a larger, more-encompassing superset of cute things.
I hope this explanation was English and helped, even if only a little and even if a month late!
Does anyone else have days where they can't get any questions right? the drills are humbling me today. Im so scared im going to get to the test and be having one of those days
Another way to think of it: sufficiency guarantees necessity not the other the way around. Being a cat guarantees being a mammal but being a mammal doesn't guarantee being a cat.
@SarahSmile That is a good way of looking at it when there is a subset and superset relationship. However, it becomes a problem in a sufficiency and necessity causal relationship. For example:
A brain death is going to get you killed (body will stop) surely i.e. is sufficient for you to get killed. But that is not necessary for you to get killed. You can get killed in all sorts of ways kidney failure, cancer etc. Death does not require brain death.
This is an example of sufficient but not necessary. That is, sufficiency is not guaranteeing neccessity because maybe there are no necessary ways to get killed.
@Ikaarin I think we’re using “necessary” in slightly different ways. In conditional logic, when we say X is sufficient for Y, we mean that Y is necessary for X. Meaning whenever X occurs, Y must occur. That doesn’t mean Y requires X in all cases. So brain death →death means that the occurrence of brain death guarantees “death” but “death” doesn’t necessarily guarantee that “brain death” occurred. Death could be the result of any other thing.
Premise 1: membership in a subset is sufficient for membership in a superset. Premise 2: X is a member of the subset. Conclusion: X is a member of the superset. Is that correct
@BreanaNunez Hi! I don't think is argument is valid.
Premise 1: If one is relaxing, they're watching tv. (Translation: If r -> tv)
Premise 2: Bre is watching TV. (Translation: B^TV)
You can't conclude that Bre is relaxing because watching TV is the necessary condition of the first premise or the "superset". This means that there are many other states that Bre or anyone could be in based on the first premise.
Another way to think about it is to think like this:
Premise 1: If one is in New York City, they're in the United States.
Premise 2: Bre is in the United States.
Based on the above logic, the conclusion would be: Bre is in New York. HOWEVER, we know that based on the premises/logic, Bre could be anywhere in the United States not just in New York.
To make the argument valid you would have to change the second premise to "Bre is in New York City" and then conclude "Bre is in the United States".
With the original argument, the same logic follows. You would have to change the second premise to "Bre is relaxing" and the conclusion to "therefore, Bre is watching TV" to make it logically sound.
You could also alter the first premise to say, "if one is watching TV, they're relaxing". Then the argument would be valid as it is.
for all of the formal logic people out there, this is is a simple argument form if you break it down into p and q. it would look something like: if p then q (p ->q), p, therefore q. this works because if the first half of a conditional statement is true (which we know it is because of the second premise, then the second half must be true in order for the statement (our original premise of if p -> q) to be true! idk if this helps anyone, but conceptually it works a lot better for me.
Back to my very first philosophy class lol! All men are mortal, Socrates is a man, therefore Socrates is mortal. Thank you philosophy degree for your help in these trying times.
Superset: mortality
Subset: all men
Socrates being a man is sufficient to say that Socrates is mortal, but being mortal isn't enough to say that Socrates is mortal, because animals and plants are mortal as well. (I think this is it)
@Sameer_Ahamad If one is a turtle, then one is a ninja, you couldn't switch the circles. If the turtle circle were on the outside, this would mean that all ninjas were turtles, and that there were even possibly some turtles that weren't ninjas, which isn't the case. If only some turtles are ninjas, then we would draw a Venn diagram with a ninja circle and a turtle circle with some overlap.
This one threw me off too. But then I remembered from an earlier video that you can only use the parameters from the question. The question says that all turtles are ninjas. In the question's universe, all turtles are ninjas (because turtle is the subset of ninjas' superset). There is no way to be a turtle without also being a ninja in this scenario.
It is possible to be a non-turtle ninja. You're right about that. Master Splinter would thus be in the superset group of ninjas, but not in the subset group of turtles. Basically, being ninja is necessary to being a turtle (all turtles are ninjas) and being a turtle is sufficient to being a ninja (all turtles are ninjas).
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97 comments
if X then
Yif
Ythen ZTherefore, X then Z
@purplesunshine007 its so funny because youre the only other person ive ever seen use this form. i worked w a tutor once and i was like oh its like a math equation like they cancel each other out and he was like ... wtf are you talking about ?? I dont have a math brain by any means but these kinds of arguments reminded me of cancelling out two-sided equations lol
@bellaens18 I’m a philosophy graduate and that’s how we were talked to validate arguments in our logic class. In the back of the book was a list of rules like that one.
@purplesunshine007 thats so good to know, we think the same LOL
I think I struggle with the distinction between VALID arguments and TRUE arguments. If the Superset of "Ninjas" includes a subset of "Turtles", which includes "Donatello" then the argument is valid that donatello is a ninja, but it is not true that all turtles are ninjas. For the the argument to be both valid and true the subset would have to be TMNT.
All Elephants are D1 Football players. Roxy is an elephant. Therefore Roxy is a D1 Football player.
Eating Buffalo Chicken Cheese Fries makes you a king. My friend ate Buffalo Chicken Cheese Fries. Therefor, my friend is a king.
@SohaS doing LSAT practice everyday will get you a high score. I'm doing LSAT practice everyday. Therefor, I will get a high score
Question Anyone? As far as the logic equation for this lesson: is B always the superset, A always subset and X always the member/membership??
@HealthLaw@28 I do believe so, yes! It seems as if formal arguments say that a member of a smaller group (subset) are always a member of a larger group (superset). Then, it plugs in an example into this smaller group to create sufficiency for membership into this larger group.
For example, "I have a cat. All cats are cute. Therefore, my cat is cute." In this example, cats (the member in question) are a subset of things that can fit into the "cute" superset label; many more things can be cute, and cats are just one of them. Saying, "I have a dog. All dogs are cute. Therefore, my dog is cute," would provide an example of another statement that expands the umbrella of "cute" things. In both examples, membership in the subset - dogs/cats - is sufficient for membership in a larger, more-encompassing superset of cute things.
I hope this explanation was English and helped, even if only a little and even if a month late!
I am confused because this just seems a lot like logic games but I am going to review it until it makes sense
Does anyone else have days where they can't get any questions right? the drills are humbling me today. Im so scared im going to get to the test and be having one of those days
@KaraSwider Yep its day 5 for me
Please don't disrespect Luke!
@MRod It's ok, Star Wars and logical reasoning don't usually go hand in hand.
Another way to think of it: sufficiency guarantees necessity not the other the way around. Being a cat guarantees being a mammal but being a mammal doesn't guarantee being a cat.
@SarahSmile That is a good way of looking at it when there is a subset and superset relationship. However, it becomes a problem in a sufficiency and necessity causal relationship. For example:
A brain death is going to get you killed (body will stop) surely i.e. is sufficient for you to get killed. But that is not necessary for you to get killed. You can get killed in all sorts of ways kidney failure, cancer etc. Death does not require brain death.
This is an example of sufficient but not necessary. That is, sufficiency is not guaranteeing neccessity because maybe there are no necessary ways to get killed.
@Ikaarin I think we’re using “necessary” in slightly different ways. In conditional logic, when we say X is sufficient for Y, we mean that Y is necessary for X. Meaning whenever X occurs, Y must occur. That doesn’t mean Y requires X in all cases. So brain death →death means that the occurrence of brain death guarantees “death” but “death” doesn’t necessarily guarantee that “brain death” occurred. Death could be the result of any other thing.
@SarahSmile I understand you now! tnx
Premise 1: membership in a subset is sufficient for membership in a superset. Premise 2: X is a member of the subset. Conclusion: X is a member of the superset. Is that correct
@VanillaCat yes!
Every conditional argument is valid? Does that also make every conditional argument true?
when you put it like this, it makes more sense.
Will the premises always be assumed true? like not all turtles are ninjas, but for the test we assume this is the case?
@SusanLeifker Oh lol it's the very next video
if one is relaxing, they're watching tv. Bre is watching TV. therefore bre is relaxing.
@BreanaNunez Hi! I don't think is argument is valid.
Premise 1: If one is relaxing, they're watching tv. (Translation: If r -> tv)
Premise 2: Bre is watching TV. (Translation: B^TV)
You can't conclude that Bre is relaxing because watching TV is the necessary condition of the first premise or the "superset". This means that there are many other states that Bre or anyone could be in based on the first premise.
Another way to think about it is to think like this:
Premise 1: If one is in New York City, they're in the United States.
Premise 2: Bre is in the United States.
Based on the above logic, the conclusion would be: Bre is in New York. HOWEVER, we know that based on the premises/logic, Bre could be anywhere in the United States not just in New York.
To make the argument valid you would have to change the second premise to "Bre is in New York City" and then conclude "Bre is in the United States".
With the original argument, the same logic follows. You would have to change the second premise to "Bre is relaxing" and the conclusion to "therefore, Bre is watching TV" to make it logically sound.
You could also alter the first premise to say, "if one is watching TV, they're relaxing". Then the argument would be valid as it is.
I hope this helps!
@BreanaNunezThis is actually known as affirming the consequent.
Finally had the light bulb moment for this section! Now let's see if I can connect the dots on PTs
for all of the formal logic people out there, this is is a simple argument form if you break it down into p and q. it would look something like: if p then q (p ->q), p, therefore q. this works because if the first half of a conditional statement is true (which we know it is because of the second premise, then the second half must be true in order for the statement (our original premise of if p -> q) to be true! idk if this helps anyone, but conceptually it works a lot better for me.
All of the Sleepless Kingdom has been cursed to sleep. Aurora is from the Sleepless Kingdom. Therefore, she has been cursed to sleep.
Back to my very first philosophy class lol! All men are mortal, Socrates is a man, therefore Socrates is mortal. Thank you philosophy degree for your help in these trying times.
Superset: mortality
Subset: all men
Socrates being a man is sufficient to say that Socrates is mortal, but being mortal isn't enough to say that Socrates is mortal, because animals and plants are mortal as well. (I think this is it)
If Troy was born in Florida, then he is American. Troy was born in America, therefore he is American
@JimmyCrosbyMalanda *Assumption: being born in America is identical to born in Florida regarding whether one is an American.
@JimmyCrosbyMalanda If one is born in Florida, then one is American.
Troy is born in Florida.
Troy must be American.
Another way to say it is: If Troy was born in Florida, then he is American. Troy is an American, Troy is not necessarily born in Florida.
If one was born in New York City, then one is American. Zach was born in NYC. Therefore, Zach is an American.
If one is a man, then one is superman. Clark Kent is a man. Therefore, Clark Kent is superman.
If one works out, they get jacked.
Mark is working out.
So, Mark will get jacked.
Subset: Getting Jacked.
Superset: Working Out.
Dexter fans:
If Dexter is the Bay Harbour Butcher, then Dexter is a serial killer.
Dexter (spoiler) is the Bay Harbour Butcher.
So, Dexter is a serial killer.
Subset: Bay Harbour Butcher
Superset: Serial Killer
Ninja - Turtle.
Can you switch the circles? Or draw the circles on top of one another? Since its not saying "Some turtles are ninjas".
@Sameer_Ahamad If one is a turtle, then one is a ninja, you couldn't switch the circles. If the turtle circle were on the outside, this would mean that all ninjas were turtles, and that there were even possibly some turtles that weren't ninjas, which isn't the case. If only some turtles are ninjas, then we would draw a Venn diagram with a ninja circle and a turtle circle with some overlap.
I felt so good about necessary vs sufficient until the ninja turtle relationship. For some reason that one keeps throwing me off.
Correct me if I'm wrong:
Subset: Turtles
Superset: Ninjas
Being a turtle is sufficient to be a ninja.
So as a turtle you are necessarily a ninja...
But it is not necessary to be a turtle to be a ninja.
Being a ninja is necessary to be a turtle.
But not all ninjas are turtles.
This one threw me off too. But then I remembered from an earlier video that you can only use the parameters from the question. The question says that all turtles are ninjas. In the question's universe, all turtles are ninjas (because turtle is the subset of ninjas' superset). There is no way to be a turtle without also being a ninja in this scenario.
It is possible to be a non-turtle ninja. You're right about that. Master Splinter would thus be in the superset group of ninjas, but not in the subset group of turtles. Basically, being ninja is necessary to being a turtle (all turtles are ninjas) and being a turtle is sufficient to being a ninja (all turtles are ninjas).
@achois1025 I like that phrase! "In the question's universe-" is a great way to think of the test's logic without bringing in your own meta knowledge