pt 58 section 4 #17

jmac800

Premise
~Nobility -----> ~ Tragedy

(~ = negative)

Conclusion

~Fate -------> ~ Tragedy

It is obvious we must link the concept of Nobility and Fate. Making D right.

My question isn't D backwards? We need an answer choice going from premise to conclusion

~nobility ------> ~ fate
Fate ------>Nobility

Instead D says
~Fate ------> ~Nobility.
Nobility -----> Fate.

Technically wouldn't this be unnecessary since it is a reversal? I know some people might say o just ignore this or look at the contrapositive, but I've seen a few questions where the contrapositive usage of it was considered wrong over the actual way. Ie. the way D had it was wrong when another answer choice said fate > nobility.

nye8870

I look at this NA question as a bridging type. The first statement says ~N --> ~T. The second says ~believes HEGF. Then concludes of "contemporary literature" ~T. So we need to bridge ~Believing HEGF to ~possessing Nobility. AC(d) says ~believe HEGF --> ~Nobility. Perfect. Furthermore, if we apply the negation test to AC(d) we get Even if an endeavor is not regarded as fate that endeavor “could” still be seen as possessing Nobility. Now you mustn’t trigger ~T.

c.janson35

P1: In order to be tragedy, must have noble protagonists.
CP: no nobility, then no tragedy

P2: No one believes that human endeavors are governed by fate.

C: Thus, contemp lit cannot be a tragedy.

It therefore cannot be the case that people don't believe endeavors are gov by fate and yet still see them possessing nobility. If it were true that people could still believe that endeavors not gov by fate could still be noble, then contemp lit could still be tragedies thus destroying the conclusion that it is impossible for contemp lit to be tragedies. This is essentially the negation of choice D, which shows why it is necessary.

Incidentally, D is also sufficient:

P1: /N-->/T
Choice /BHEGBF--->/N
P3: we know /BHEGBF

Therefore we know that /T must be true transitively.


Hope this helps!

c.janson35

Also, you said: "~nobility ------> ~ fate
Fate ------>Nobility

Instead D says
~Fate ------> ~Nobility.
Nobility -----> Fate.

Technically wouldn't this be unnecessary since it is a reversal? I know some people might say o just ignore this or look at the contrapositive, but I've seen a few questions where the contrapositive usage of it was considered wrong over the actual way. Ie. the way D had it was wrong when another answer choice said fate > nobility."

This isn't the contrapositive of what you said, it's the incorrect reversal. The contrapositive of a conditional relationship will never be wrong if the original conditional relationship is what you are looking for because the contrapositive is logically identical. This also means that the incorrect reversal will not be right because it confuses the logical meaning of the statement.

Hope this helps (again)!