It is clear that none of the volleyball players at yesterday's office beach party came to work today since everyone w...

Slade August 20, 2020

Hello, I don't understand option B for this question

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 August 20, 2020

wait is it because the only conclusion that would make this valid would be om -> not P?

shunhe August 21, 2020

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.