No small countries and no countries in the southern hemisphere have permanent seats on the United Nations Security Co...
MazenApril 1, 2020
Please Help: Can't I Deduce E by combining the two Suff.-Nec. Principles?
Hello,
Diagramming the stimulus exactly the same way as the video, we get the following diagrams:
First principle rule:
SC------->~PS
PS------->~SC
Second principle rule:
SH------->~PS
PS------->~SH
Third principle rule:
PS------>FInc.IP + F>RD
~F>RD or ~FInc.IP------->~PS
Fourth principle rule (a quantifier):
FInc.IP--some--~Inc.SR
~Inc.SR--some--FInc.IP
Okay: I inferred E but from the lecture, I leaned that:
If A, then B
If A, then C
Assuming the existence of one A, it must therefore follow that: B--some--C
So, principle three can be broken up into:
3.a) PS---->FInc.IP
and
3.b) PS---->~>RD
Combining principle rule 3.b and the contrapositive of the second principle rule: PS----->~SH
assuming the existence of a PS, we can infer E
~SH--some--~>RD
Is this a sound alternative logic to the video?
thank you
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I think there might be a mistake here regarding principle 3b. We've established that every country with a permanent seat DOES want the UN to have a greater role in moderating regional disputes.
So, shouldn't you diagram it without the negative (~): PS ---> >RD
Maybe I've just misread your diagram here, because everything else looks good and it led you to the right answer.
Basically, you presented two characteristics of every country with a permanent seat. 1. None of them are in the southern hemisphere. (~SH) 2. All of them are in favor of UN moderating RD. (> RD)
When we have two "all" or "most" characteristics of the same group, I like to say that there will be "overlap." In other words, we can conclude that some countries not in the southern hemisphere are in favor of UN moderating regional disputes. Which countries? Those with a permanent seat on the council.
MazenApril 8, 2020
Hello Sam,
Yes I should have diagram it without the negative 3b: PS-----> >RD. It is a typo, though. What and how I meant and applied it is correct. So, the error does not affect the logical conclusion.
Assuming the existence of one PS, when we combine the correct diagramming of 3b (PS------> >RD) with the second principle rule (PS----> ~SH), then we can conclude >RD--some--~SH, or, ~SH--some-->RD which is E: "Some countries that are in favor of a greater role for the United Nations in moderating regional disputes are not located in the southern hemisphere."
But your point is well taken! My apprehensiveness is to unwarrantedly assuming the existence of the sufficient in the case of two "all" statements, or, again assuming the existence of the left side of two "most"statements.
In retrospect, I started the discussion because the way, I believe Naz, has E concluded is interesting and led me to question whether I am incorrectly assuming the existence of one PS (permanent seat). I do not think I am. I repeatedly read the stimulus.
