Q2 - Advertisement: Anyone who thinks

[WaltGrace1983]

~(moisture for the ground - "the skin of the earth") → ground becomes lined, cracked, and liveliness fades
→
Your skin too should be protected

This argument is laughable. It is basically saying that, because dryness of the ground leads to particular consequences, dryness of your skin leads to the same consequences. Now this may or may not be true. However, the argument is flawed in the sense that we are comparing two things that are not sufficiently alike.

(A) Wrong flaw. If this were the flaw, the argument would say something like "Every time you don't use this moisturizer in the morning, your skin gets dry. Your skin is dry today. Thus, you didn't use this moisturizer this morning."

(B) Wrong flaw. There is nothing causal that needs to be addressed here.

(C) Wrong flaw. Changing what people think is not addressed.

(D) Wrong flaw. The term "infusion is not relevant to the reasoning."

(E) Correct! This is getting at the flaw assuming that there is sufficient similarity between the ground and your skin.

[griswald]

Can someone help me more deeply understand why (A) is the wrong flaw? I started out with (E) as my answer but later on after thinking through the problem, I changed it to A.

Here was my reasoning:
"Without regular infusions of moisture the ground becomes lined and cracked and its lush loveliness fades away."

I diagrammed this as:
-(lined and cracked) ---> regular infusions of moisture

Then since the advertisement seems to say that if you use the product, you protect your skin, I wrote the diagrammed conclusion as:
regular infusions of moisture ---> -(lined and cracked)

Which would be an incorrect necessary-sufficient flaw...

[ohthatpatrick]

Great question.

(A) is the ol' Nec/Suff flaw, which (as you seem to know) just means that there was a conditional statement in the premise, but the author's reasoning reflects an illegal negation or reversal of it.

The problem with your rationale is when you said "it seems to suggest that IF you use this product, you WILL be protected".

Naturally, that's a normal way for a consumer to hear/interpret an advertisement.

But this is nitpicky LSAT and there are no conditional words in the author's final sentence.

I can say
"Without studying for LSAT, you're not going to get a 180. Thus, you should study for LSAT."

That's not committing me to any logical fallacy of saying
IF you study, you WILL get a 180.

It's possible to identify something as needed and then recommend that someone attain that needed thing, without guaranteeing any results.

If you wanted to really fight for (A), you might say that Dewyfresh, "the drought-defying moisturizer", sounds like a guarantee of "If you use this moisturizer, you defy droughts".

But if LSAT was going to test Nec/Suff, it would need to be more explicit:
"So anyone who uses regular infusions of Dewyfresh is bound to avoid the ravages caused by lack of moisture."

I sympathize with you that this question is not written very well. First of all, I think you're right in identifying that "regular infusions of moisture" is identified as something necessary . And the gist of the advertisement is that regular infusions of Dewyfresh would would give you the protection you want.

Finally, I actually DON'T think it's that flawed of an analogy to say that without moisture, both ground and skin become lined and cracked.

So I can't totally make you not hate this. I would just remind you of my earlier thought that any time they've ever tested Nec/Suff, it's way more explicit in terms of showing that one thing guarantees another thing.

We shouldn't have to resort to "it SEEMS to say ...".

Hope this helps.

[PepitoH243]

I thought A was correct because I thought that moisturizing was necessary to get a beautiful skin. Which is the case in actual life. Usually analogies are made with hyperboles so I don't find how this answer makes sense.