The author uses the word "immediacy" (line 39) most likely in order to express
Tateon December 2, 2022
Missing Premise Drills
Please help me to understand, maybe I'm over thinking this, but I'm afraid I missed something......
I feel as if I worked through this as advised but, I don't understand why some of the answer cards have a positive and contrapositive listed in what I would consider opposite of one another. (I worked this one out and concluded that it would be the positive, but the answer card lists it as a contrapositive or visa versa). The flash card has the third premise on this missing premise question written as the answer being:
# 3 P: Z--->D
(~D--->~Z)
My working through the problem comes out this way:
#1P: C--->E * *
(~E--->~C) ~Z ~E
* *
#2P: E--->Z ~D ~C
(~Z--->~E) |------------------------>|
#3P: ?
Solved to be ~D--->~Z (Opposite of the answer or what I listed above)
(Z--->D)
#1C: ~D--->~C
(C--->D)
Can you help me fine tune?
I understand I used the contrapositive of premise 1 to get from ~E--->~C
Then, I used the contrapositive of premise 2 to get from ~Z--->~E because of this, I was able to recognize the missing premise is then, ~D--->~Z.
What confuses me is why the answer card lists ~D--->~Z as the contrapositive of Z--->D and not the positive answer to premise 3, when the known conclusion is known ~D--->~C / (C--->D).
Thank you for your assistance.
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I can see there are some significant formatting issues between the message box my question was written into to here where it changed and displayed my diagrams to nothing like I wrote it out. I tried diagramming when I originally wrote this question using the technique Rob Smoot taught in Missing Premise Office Hours i.e. Getting from ~D ~C, placing ~E and ~Z up above showing me the path to the missing premise ~D--->~Z.
Tateon December 3, 2022
I re-watched Rob's office hours and I saw that he actually covered the same problem. I re-listened to his explanation for this flashcard problem and then another problem where the same thing occurred to him and I am comfortable knowing, whichever way it is written, it's means the same thing.
