Does anyone feel like these kind of mental gymnastics are like equations? In that case, I'm not a fan of this kind of math lol. All I can deduce this is into is just standard sentences: Anyone who eats expired food--> gets sick. I ate expired food. Therefore, I get sick.
If the subscript is messing some people up, in my mind, writing out the contrapositive statement is really helpful. At the end of the day, we can only move from the left side of the arrow to the right. If we diagram that out clearly, I think it is difficult to go wrong
I remember taking a logic class in college and we used the negation symbol as this ~ and not the slash/. I think the slash is throwing me off in these lessons a little bit. Either way I am realizing that logic class actually helped me a lot.
At first I felt like some of these videos are super repetitive. Now I see that I never would have understood that if Luke is a Jedi and Jedi use the force that Luke uses the force.
Contradictorily
If Luke cannot use the force and Jedi use the force. Luke is not a Jedi.
so basically the form of the argument takes precedent over whether the argument is true or not (valid) to the real world. if the form of the argument is the same, the argument must be thought of as true. (right?)
@VenessaO77 It might be my lack of sleep and food, but what does "though of as true" mean? Other than that, I think you're correct. Determining the form of the argument is the most important thing when you're figuring out how to tackle it. If the argument states "All bears are pink. Luna is a bear, therefore she is pink" the argument is valid, just not true.
@Narmis The argument isn't valid in your example because being tall isn't necessary for being good at baseball (at least not according to your premise). So while knowing someone is tall is sufficient to know they play baseball, knowing someone plays baseball is not sufficient to know they are tall.
Instead, it would be
T ---> B (if one is tall, they must be good at baseball)
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The above are valid, the contrapositive is just modus tollens.
To do so, simply reverse then negate:
The only exception is where conditions are independent (or), they become joint (and): 
The above are valid, the contrapositive is just modus tollens.
To do so, simply reverse then negate:
The only exception is where conditions are joint: 
I am truly hoping I don’t NEED this lawgic to pass. This has made more sense in words and I really do not need formulas to add to the confusion.
so is there a contraposition argument within a conditional argument if you negate or are they two separate things
I UNDERSTAND 🤝🏾
Has anyone else found it easier to just rename the visual sets to /(variable) and inverting the set order when doing lots of work on contrapositives?
Does anyone feel like these kind of mental gymnastics are like equations? In that case, I'm not a fan of this kind of math lol. All I can deduce this is into is just standard sentences: Anyone who eats expired food--> gets sick. I ate expired food. Therefore, I get sick.
Makes sense mostly.
I wrote off me and contrapositives a looooong time ago, but this actually makes sense!!
If the subscript is messing some people up, in my mind, writing out the contrapositive statement is really helpful. At the end of the day, we can only move from the left side of the arrow to the right. If we diagram that out clearly, I think it is difficult to go wrong
A --> B
X = A
X --> B
is the same thing as
A --> B
/B --> /A
X --> /A
I remember taking a logic class in college and we used the negation symbol as this ~ and not the slash/. I think the slash is throwing me off in these lessons a little bit. Either way I am realizing that logic class actually helped me a lot.
If one prepares for the LSAT, then one is going to law school. Sarah is not going to law school; therefore, Sarah does not prepare for the LSAT.
LSAT→LS
s/LS
______
s/LSAT
All these math symbols are throwing me off
@SofiyaBerman yea im over all that, ill see how i fare
if one is a dancer, then one is an athlete.
D > A
Mike is not an Athlete
m^/A
________
m^/D
Therefore, Mike is not a dancer
If one eats a thousand donuts, then one must perform in the circus
TD>C
Nina did NOT perform in the circus
n^/C
------
n^/TD
Therefore, Nina did NOT eat a thousand donuts
At first I felt like some of these videos are super repetitive. Now I see that I never would have understood that if Luke is a Jedi and Jedi use the force that Luke uses the force.
Contradictorily
If Luke cannot use the force and Jedi use the force. Luke is not a Jedi.
Beginning to learn I am.
@fjnathaniel This is the way.
modus tollens
p-->q
~q
therefore ~p
so basically the form of the argument takes precedent over whether the argument is true or not (valid) to the real world. if the form of the argument is the same, the argument must be thought of as true. (right?)
@VenessaO77 It might be my lack of sleep and food, but what does "though of as true" mean? Other than that, I think you're correct. Determining the form of the argument is the most important thing when you're figuring out how to tackle it. If the argument states "All bears are pink. Luna is a bear, therefore she is pink" the argument is valid, just not true.
@kyorofan20 thought*
So is it fair to say that the conditional form represents a sufficient argument and the contrapositive form represents a necessary argument?
Everyone who is tall (T) is good at baseball (GB).
(T > GB)
S (s) is tall.
(s^T)
S is good at baseball.
(sGB)
C (c) is not tall.
(c/T)
C is not good at baseball.
(c/GB)
Is this right?
@Narmis The argument isn't valid in your example because being tall isn't necessary for being good at baseball (at least not according to your premise). So while knowing someone is tall is sufficient to know they play baseball, knowing someone plays baseball is not sufficient to know they are tall.
Instead, it would be
T ---> B (if one is tall, they must be good at baseball)
which can be arranged to:
/B ---> /T
so if....
/B ---> /T
and Maia (/B)
then
Maia (/T).
If one has supernatural powers, they've eaten a devil fruit. SP-->DF
Luffy has supernatural powers. l^SP
Luffy has eaten a devil fruit. l^DF
Contrapositive:
SP-->DF
Usopp does not have supernatural powers. u^/SP
Usopp has not eaten a devil fruit. u^/DF
All dogs like bacon
Kitty does not like bacon
Kitty is not a dog
Am i doing this right?
@kimwexler Yes!
Dog → Likes Bacon
Kitty /Likes Bacon
____
Kitty /Dog
All fishes stink
Sandy does not stink
Sandy is not a fish
Is this correct??
@Jcruzmed Yep! F->S, s^/S, therefore s^/F.
I'm not sure of anyone else has pointed it out, but is it fair to say that the contrapositive argument structure models that of "modus tollens"?
P1: All cats are annoying
P2: Peter is not annoyin
C: Peter is not a cat