i don't understand why you can't split the arrow when there's a disjunction in the necessary condition. Is it because only one of the two can happen when the or is in the necessary condition?
Is it intentional that we are not immediately diagramming the counterfactuals for these? Would be helpful to confirm our logic. For example in the last example I initially plotted " M --> N OR O" which I assume is the counterfactual to "/N OR /O --> /M" #feedback thanks
Small problem I think with the last example, the speaker interprets "If N or O are not adopted" as /N or /O, but I believe the more accurate translation would be /(N or O) because it seems to me that the statement says that it is not the case that N or O are adopted, which then would translate into /N and /O by demorgan's. I am sure I am making a mistake somewhere, but I have looked over the comments and the question many times and I cannot figure it out, any advice? #help
Can someone help me with disjunction in the necessary condition? How is it possible that if I say something like
If it's Tuesday, then the store has a sale on liquor or tomatoes
Tu → Li or To
How could OR be used in this way and it's a possibility that on a Tuesday they run a sale on both liquor and tomatoes? Wouldn't OR mean that it needs to be one or the other, but cannot be both?
#help for the second example "If N or O is not adopted, then M cannot be adopted.," why does "cannot" not trigger the group 4 rule (pick idea and negate necessary condition)?
#feedbackHELP!!!! Okay need someone to help for this. Do I have this correct. A--B or C. Do we know that if they tell us that A happened and we know that B didn't happen then what must be true is that C happened right.
#Help What if it is said "If N or O is adopted, then M will be adopted."? Would that mean that if N is adopted but O is not, M is adopted? Or do both have to be adopted? I believe it would work if just one is but not sure.
I understand that one of two sufficient conditions is enough to fulfill the necessary condition, but I am struggling to understand how two conditional claims in the necessary condition with one sufficient condition create a valid argument? Any insight team?
I kinda understand but I might get it confused with the conjunctive 'and' since it seems to me like necessary and sufficient are opposite with and & or?
I’m still a little confused hopefully someone can help me out with the first example. If the Chancellor succeeds that means that Amidala failed or the Jedi’s failed. So we’re saying that it’s necessary for Amidala or the Jedi to fail or both. I think my confusion is not being able to split the arrow, is it that CS-> AF or CS-> JF reads Chancellor succeeds so Amidala failed or Chancellor succeeds so Jedi’s failed.
So are we operating from a place of assumption? Basically assuming that since the Chancellors plan succeeded that either Amidala failed or JF failed.
So either one of two options failed or both and we know that that happened because the chancellor plan succeeded.
If I’m speaking in circles I apologize I am just trying to understand it in as simple terms as possible.
I'm having difficulty understanding why disjunction in the necessary condition can't be visually represented by "splitting the arrow."
The first example states, "If the Chancellor's nefarious plan succeeds, then either Amidala failed to convince the Senate or the Jedi Knights failed their mission." According to 7Sage, "at least one (but possibly both) of the two conditions must trigger when the sufficient condition triggers." Couldn't that be drawn like this?
AF
↗
CS
↘
JF
In this diagram (at least, the way I'm interpreting it), the Chancellor's plan succeeding (CS) could trigger Amidala failing to convince the Senate (AF). It could trigger Jedi Knights failing their mission (JF). Alternatively, it could trigger BOTH AF and JF. Doesn't that accord with this statement: "At least one (but possibly both) of the two conditions must trigger when the sufficient condition triggers"?
I have a hypothesis about what my misunderstanding might be. Perhaps the diagram above implies that BOTH AF and JF will trigger if CS is triggered (which doesn't leave room for the "or" interpretation). In other words, the way I've drawn it suggests that AF and JF can't happen independently of each other (BOTH must happen if CS happens, which isn't what the sentence says). Is that where I'm going wrong?
#help
EDIT: Sorry my diagram isn't showing up properly, but you get what I'm trying to say haha.
Putting an example using negatives under the disjunction in the sufficient condition header added an unhelpful level of complexity. The content appears to describe that omitting either element of a sufficient disjunctive negates the possibility of triggering the necessary condition.
These examples would be much more helpful if they were kept in the same context. For example, if the sufficient condition were illustrated here using the “If the Chancellor's nefarious plan…” bit. That would allow the reader to compare them instead of trying to compare two different sentences while learning the concept.
I'm a bit confused about how the second example shows that the sufficient condition is independent of each other but why doesn't the necessary condition on the first example also serve as independent of each other if only one is necessary?
Hi this might sound like a really stupid question but im lowkey struggling. I got to the "kick it up" lesson and was hopelessly lost so I went back to review everything beforehand and I think I'm just lacking solidity on the difference between a necesary conditon and the sufficient condition.
For example 2: If N or O is not adopted then M cannot be adopted.
It's saying that the disjunction is in the sufficient conidition so that means that N or O not being adopted is the sufficient condition. Couldn't you just as easily flip it and say that If M was not adopted then that means that either N or O were also not adopted? If so that does that change the sufficient condition to being M not being adopted? Or would it stay as N or O?
#help Just to clarify, is there any difference between the "or" being used in the sufficient in this example and the "or" we have classified in Group 3 (negate sufficient)?
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60 comments
OR in necessary = DON'T SPLIT
AND in necessary = You can split
OR in sufficient = You can split
AND in sufficient = DON'T SPLIT
(I hope this is right...correct me if needed)
i don't understand why you can't split the arrow when there's a disjunction in the necessary condition. Is it because only one of the two can happen when the or is in the necessary condition?
I am confused by the sufficient disjunction. Do you need BOTH /N and /O to have /M? Or is it correct to say that /N --> /M OR /O --> /M?
Is it intentional that we are not immediately diagramming the counterfactuals for these? Would be helpful to confirm our logic. For example in the last example I initially plotted " M --> N OR O" which I assume is the counterfactual to "/N OR /O --> /M" #feedback thanks
Small problem I think with the last example, the speaker interprets "If N or O are not adopted" as /N or /O, but I believe the more accurate translation would be /(N or O) because it seems to me that the statement says that it is not the case that N or O are adopted, which then would translate into /N and /O by demorgan's. I am sure I am making a mistake somewhere, but I have looked over the comments and the question many times and I cannot figure it out, any advice? #help
would it also make sense to visualize it like this?
If A, then B or C.
A
--> B
--> C
--> B and C
(imagine the arrows are all coming from the "A" lol)
#feedback please allow for the adjustment of the font size on closed captions! They take up so much space on the screen, it is distracting.
Can someone help me with disjunction in the necessary condition? How is it possible that if I say something like
If it's Tuesday, then the store has a sale on liquor or tomatoes
Tu → Li or To
How could OR be used in this way and it's a possibility that on a Tuesday they run a sale on both liquor and tomatoes? Wouldn't OR mean that it needs to be one or the other, but cannot be both?
#help for the second example "If N or O is not adopted, then M cannot be adopted.," why does "cannot" not trigger the group 4 rule (pick idea and negate necessary condition)?
#feedbackHELP!!!! Okay need someone to help for this. Do I have this correct. A--B or C. Do we know that if they tell us that A happened and we know that B didn't happen then what must be true is that C happened right.
#Help What if it is said "If N or O is adopted, then M will be adopted."? Would that mean that if N is adopted but O is not, M is adopted? Or do both have to be adopted? I believe it would work if just one is but not sure.
So, in:
If N or O are not adopted then M is not adopted.
Ans:
/N or /O -> /M
/N -> O and /O -> N
so , conclusion scenario 1- N -> /O -> M
conclusion scenario 2- O -> /N -> M
So, am I right if I am analyzing it this way?
I understand that one of two sufficient conditions is enough to fulfill the necessary condition, but I am struggling to understand how two conditional claims in the necessary condition with one sufficient condition create a valid argument? Any insight team?
I kinda understand but I might get it confused with the conjunctive 'and' since it seems to me like necessary and sufficient are opposite with and & or?
I’m still a little confused hopefully someone can help me out with the first example. If the Chancellor succeeds that means that Amidala failed or the Jedi’s failed. So we’re saying that it’s necessary for Amidala or the Jedi to fail or both. I think my confusion is not being able to split the arrow, is it that CS-> AF or CS-> JF reads Chancellor succeeds so Amidala failed or Chancellor succeeds so Jedi’s failed.
So are we operating from a place of assumption? Basically assuming that since the Chancellors plan succeeded that either Amidala failed or JF failed.
So either one of two options failed or both and we know that that happened because the chancellor plan succeeded.
If I’m speaking in circles I apologize I am just trying to understand it in as simple terms as possible.
Is saying "inclusive or" the same thing as saying "and or"?
I'm having difficulty understanding why disjunction in the necessary condition can't be visually represented by "splitting the arrow."
The first example states, "If the Chancellor's nefarious plan succeeds, then either Amidala failed to convince the Senate or the Jedi Knights failed their mission." According to 7Sage, "at least one (but possibly both) of the two conditions must trigger when the sufficient condition triggers." Couldn't that be drawn like this?
AF
↗
CS
↘
JF
In this diagram (at least, the way I'm interpreting it), the Chancellor's plan succeeding (CS) could trigger Amidala failing to convince the Senate (AF). It could trigger Jedi Knights failing their mission (JF). Alternatively, it could trigger BOTH AF and JF. Doesn't that accord with this statement: "At least one (but possibly both) of the two conditions must trigger when the sufficient condition triggers"?
I have a hypothesis about what my misunderstanding might be. Perhaps the diagram above implies that BOTH AF and JF will trigger if CS is triggered (which doesn't leave room for the "or" interpretation). In other words, the way I've drawn it suggests that AF and JF can't happen independently of each other (BOTH must happen if CS happens, which isn't what the sentence says). Is that where I'm going wrong?
#help
EDIT: Sorry my diagram isn't showing up properly, but you get what I'm trying to say haha.
When are the suffients of a disjunction not independent of each other?
Putting an example using negatives under the disjunction in the sufficient condition header added an unhelpful level of complexity. The content appears to describe that omitting either element of a sufficient disjunctive negates the possibility of triggering the necessary condition.
Does anyone know why we are not using logic symbols? Ex: ~ is the logic symbol for not and v is the logic symbol for or.
We learned before that (Or) in the LSAT means and/or = cloud be both but at least one.
So, why does (or ) here in conditions means (or) only??
These examples would be much more helpful if they were kept in the same context. For example, if the sufficient condition were illustrated here using the “If the Chancellor's nefarious plan…” bit. That would allow the reader to compare them instead of trying to compare two different sentences while learning the concept.
#help
I'm a bit confused about how the second example shows that the sufficient condition is independent of each other but why doesn't the necessary condition on the first example also serve as independent of each other if only one is necessary?
Hi this might sound like a really stupid question but im lowkey struggling. I got to the "kick it up" lesson and was hopelessly lost so I went back to review everything beforehand and I think I'm just lacking solidity on the difference between a necesary conditon and the sufficient condition.
For example 2: If N or O is not adopted then M cannot be adopted.
It's saying that the disjunction is in the sufficient conidition so that means that N or O not being adopted is the sufficient condition. Couldn't you just as easily flip it and say that If M was not adopted then that means that either N or O were also not adopted? If so that does that change the sufficient condition to being M not being adopted? Or would it stay as N or O?
#help Just to clarify, is there any difference between the "or" being used in the sufficient in this example and the "or" we have classified in Group 3 (negate sufficient)?