Hello, I don't understand option B for this question
Started by
Slade
· started 2020-08-20 01:24
· last activity 2020-08-21 01:43
· 2 replies
Can I get a better explanation of why this answer is invalid? I have watched that part of the explanation video multiple times and still do not understand.
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Slade
· 2020-08-20 02:03
wait is it because the only conclusion that would make this valid would be om -> not P?
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shunhe
· 2020-08-21 01:43
Hi @Slade,
Thanks for the question! So diagramming the original stimulus, we see that the structure is
Volleyball —> Badly sunburned
Work today —> ~Badly sunburned
Therefore: VP —> ~Work today
Which can be abstracted to
A —> B
C —> ~B
Therefore: A —> ~C
Which we get by (for example) taking the contrapositive of the second statement and then linking it to the first statement.
Now let’s take a look at (B). Diagramming this, we get
Promoted —> ~Fail to attend awards banquet
Office manager —> ~Promoted
Therefore: Office manager —> Fail to attend awards banquet
Which can be abstracted as
A —> ~B
C —> ~A
Therefore: C —> B
Which is obviously different from the first construction, and actually not even a valid argument (unlike the stimulus). Thus, for this parallel reasoning question, (B) is wrong.
Hope this helps! Feel free to ask any other questions that you might have.
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