Humans' emotional tendencies are essentially unchanged from those of the earliest members of our species. Accordingly...

MikeND on October 20, 2020

Hi Vennela! I'm not an instructor but I think I know the answer to your question. D is wrong because, in Strengthen with a Necessary Premise questions, we first need to check if the answer choice will Strengthen the argument (and then we negate to verify that the choice will destroy the argument).

Looking at D, it does not strengthen the argument because humans choosing on the basis of their emotions alone is irrelevant to the conclusion that (despite more choices nowadays) humans are now unable to choose more wisely. On the other hand, E is correct because it both strengthens the argument and its negation (in this case, showing existence of the sufficient condition without the necessary) directly supports the first premise, that humans' emotional tendencies are unchanged and thus we're unable to choose more wisely.

Hope this helps!

Mazen on July 16, 2022

Hi

I am not a tutor either. But I respectfully disagree with Michael that D does not strengthen.

D, as I understand it, does strengthen the argument; in fact it is too strong: emotions alone are responsible for humans to "generally be unable to make wise decision." (side note, the word "generally" is weaker than an if-->then conditional.)

However, even though D strengthens the argument, it is the wrong answer-choice because it is not necessary for the conclusion. Proof: when negated, not only does D's negation not weaken, let alone destroy the argument, it may strengthen the argument in its negative form!

The negation test follows:

D states: "Regardless of the range of choices available to humans, they choose on the basis of their emotions alone."

Negation of D is: Regardless of the range of choices available to humans, they do not choose on the basis of their emotions alone. "Not choosing on the basis of emotions alone" means there are other factors.

But even if there are other factors, what if emotions constitute the primary factor. So, we negated D, we inferred from the negation that there are other factors, and yet we can still have emotions in the context of the negated answer-choice D strengthening the argument by virtue of emotions being the primary factor among the bunch!

Having said all that, as I said at the outset of this post, I am not an instructor.

Respectfully,
Mazen