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?)
I dont really understand how we got Athena like where dod we just pull that out of and how is that in the slightest way related to proving the argument
I often find myself confused as to how these concepts could be applied to the actual exam or exam questions- I understand that as a core course these videos are meant to lay a foundation but I would love to see more complex examples that reflect logical questions on the exam at the end of most videos to begin applying the concepts early on. It would help me understand why this is important and where I will be using it.
#feedback Some of the videos allow you to switch to full screen, fast forward, change the speed, etc. while other videos do not. I tried refreshing the page but that only worked once. Can this issue be resolved?
I feel like the explanation is super wordy simply it is
a conditional statement
If one lives in NYC than they live in the USA
NYC → USA
Contrapositive just flip and slash
/USA → /NYC
so NOT in the USA than NOT in NYC
in a statement, the contrapositive is as follows
If one lives in NYC then one lives in the USA. Dave does not live in the USA. Therefore Dave does not live in NYC. As you can see from our contrapositive statement above this follows that exact form. This is valid.
Does it remain that the Force is the necessary condition always, in that contrapositive relation? I just internalized that the left side of the arrow is the sufficient condition and the term on the right is the necessary, but when flipped in a contrapositive it seems like the necessary condition remains, i.e. in the argument /F --> /J, I read this as /F as the sufficient condition in this case, but the narrative above does not make that distinction clear for me at least, if someone knows can they clarify?
Am I correct in saying that with conditional arguments, we are working with the subset --> superset, and then with contrapositive arguments, we are working with the superset --> subset?
i get it. But it seems like the explanation is a bit too wordy.
Flip and Negate.
If A then B
X is in A
Therefore, X is in B
Contrapositive now (Flip and Negate)
If not B then not A
X is not in B
Therefore X is not in A
(Plse correct me if im wrong)
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57 comments
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?)
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?
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?
All fishes stink
Sandy does not stink
Sandy is not a fish
Is this correct??
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
All dogs are cute
Joe is not cute
Joe is not a dog
Premise 1: if a plant is a flower, then it is pretty.
Premise 2: the plant is not pretty.
Conclusion: the plant is not a flower
Is this correct ???
I dont really understand how we got Athena like where dod we just pull that out of and how is that in the slightest way related to proving the argument
I often find myself confused as to how these concepts could be applied to the actual exam or exam questions- I understand that as a core course these videos are meant to lay a foundation but I would love to see more complex examples that reflect logical questions on the exam at the end of most videos to begin applying the concepts early on. It would help me understand why this is important and where I will be using it.
#feedback
#feedback Some of the videos allow you to switch to full screen, fast forward, change the speed, etc. while other videos do not. I tried refreshing the page but that only worked once. Can this issue be resolved?
Question: How would I use this on the LSAT? They show visuals on the test?
For chaining a contrapositive, I have created the following example:
If one is tall then one is smart if one is smart then they have a big brain (T --> S --> B)
Contra: If one does not have a big brain then one is not smart and therefore is not tall (/B --> /S --> /T)
and
If one is annoying then they talk a lot, if one talks a lot then they are not smart (A --> T --> /S)
Contra: If one is smart then they do not talk a lot, and they are not annoying (S --> /T --> /A)
Are these examples correct or incorrect? How does one create a contrapositive of a chain or is one unable to do so.
Thanks and let me know.
I feel like the explanation is super wordy simply it is
a conditional statement
If one lives in NYC than they live in the USA
NYC → USA
Contrapositive just flip and slash
/USA → /NYC
so NOT in the USA than NOT in NYC
in a statement, the contrapositive is as follows
If one lives in NYC then one lives in the USA. Dave does not live in the USA. Therefore Dave does not live in NYC. As you can see from our contrapositive statement above this follows that exact form. This is valid.
I understood everything except when it came to introducing Formal Argument 2
Does it remain that the Force is the necessary condition always, in that contrapositive relation? I just internalized that the left side of the arrow is the sufficient condition and the term on the right is the necessary, but when flipped in a contrapositive it seems like the necessary condition remains, i.e. in the argument /F --> /J, I read this as /F as the sufficient condition in this case, but the narrative above does not make that distinction clear for me at least, if someone knows can they clarify?
All Canadians like Don Cherry's suits.
John doesn't like Don Cherry's suits.
John isn't Canadian.
Using slashes instead of just crossing things out is kinda silly and prob confuses new students a little.
All banking buildings are downtown.
Building A is not downtown.
Building A is not a banking building.
Vegans don't eat meat. If John eats tofu every time I see him at lunch, then he must be a vegan.
Eating tofu → Being vegan
Vegans don't eat meat. If John wasn't a vegan, then he would not eat tofu every time I see him at lunch.
Not being a vegan → Not eating tofu
Did I get that right?
#help
Am I correct in saying that with conditional arguments, we are working with the subset --> superset, and then with contrapositive arguments, we are working with the superset --> subset?
i get it. But it seems like the explanation is a bit too wordy.
Flip and Negate.
If A then B
X is in A
Therefore, X is in B
Contrapositive now (Flip and Negate)
If not B then not A
X is not in B
Therefore X is not in A
(Plse correct me if im wrong)