Dr. A: The new influenza vaccine is useless at best and possibly dange

Info from the text: “The vaccine is useless” because “the vaccine is worthless” i.e. no reason is given

A) “The vaccine is unsafe” because “three patients have been harmed” some sort of reasoning is present

B) JJ recommends this milk BUT SINCE i don’t trust this ninja i won’t buy this milk – a reason is there: this ninja is not trustworthy source for info

C) WingzZ balls perform better because they are “far more effective than others” i.e. better. So WingzZ get to perform Better because they are Better.

D) I buy VVs because doctor recommends them more often because blah blah -- I bought a Yugo car because my best friend recommended it.

E) Reason is given

Thus C is the answer.

I agree with Hades that this type of question is much more likely to appear on the LSAT than on the GMAT. In fact, on the LSAT, the question stem would ask "which of the following displays FLAWED reasoning most similar to that of Dr. A?"

That said, C is the best answer.

Dr. A is taking as a given (evidence) that the vaccine is useless, and then basing his or her conclusion about the studies on that evidence. This is flawed because the studies should be judged to be true or false regardless of any preconceived notion about the vaccine.
Likewise, answer choice C is claiming as evidence that Wingzz tennis balls are the most effective, and then basing its conclusion, "they perform best," on that evidence; the same backwards reasoning shown in the prompt. The performance of tennis balls is not BASED on their effectiveness, it is the thing that tells us how effective they are, just like the studies should tell us whether the vaccine works or not.

The only other viable choice, B, is incorrect because it displays a different distinct flaw, common on the LSAT: attacking a speaker rather than a speaker's ideas. There is no analogue to "Jerrold Jersey" (a person whose opinion should not be trusted) in the prompt. In the prompt, the attack on the studies is impersonal, based on a generalization. In B, the attack on Jerrold Jersey IS the generalization.

Alex
Knewton Verbal Developer

this is circular reasoning, i.e., someone is stating something is effective because he thinks it's effective. That someone didn't mention why it's good or effective, and his only reasoning for it is because he thinks it's good. In this questions we need to look for reasoning similar to that. In C there is no mentioning why he thinks the balls are good; he just thinks they are effective.
so the answer is C

The crux of this argument is that the logical reasoning of this argument is at fault. So we need to find an answer option who logical reasoning is at fault.
Dr. A: The studies must have been faulty because the vaccine is worthless.
The vaccines can be faulty and that is why the studies is worthless.. nor the other way around.


(A) Three of my patients have been harmed by that vaccine during the past three weeks, so the vaccine is unsafe.
Logical

(B) Jerrold Jersey recommends this milk, and I don’t trust Jerrold Jersey, so I won’t buy this milk.
Logical

(C) Wingzz tennis balls perform best because they are far more effective than any other tennis balls.
Logical

(D) I’m buying Vim Vitamins. Doctors recommend them more often than they recommend any other vitamins, so Vim Vitamins must be good.
Logical

(E) Since University of Muldoon graduates score about 20 percent higher than average on the GMAT, Sheila Lee, a University of Muldoon graduate, will score about 20 percent higher than average when she takes the GMAT.
Illogical. Gmat scores depends on your personal capability and not in your college name.

ERROR..
I couldn't understand these kinda questions ...totally confused in all the given options. Even after reading this question thrice ,my mind goes with option B and not C...IS IT WISE TO LEAVE SUCH QUESTIONS IN EXAM???

If you don't want to score above V40 then yes, otherwise a big NO.

Hi. Can anyone help explaining why ain't the reasoning Strawman instead ?

Dr. A try to falsify the argument with no clear understanding, which can be easily broken by DR. B

Can anyone explain how is Stimulus circular reasoning?

Posted from my mobile device

Dr A is performing what is known as an Informal Logical Fallacy nicknamed “Begging the Question.”

Basically this occurs when the author’s Premises aren’t used as support for the Conclusion: the argument’s premises already assume that the conclusion is true.

The author has already assumed the truth of his conclusion, rather than providing any support for the conclusion.

“Running helps you lose weight because running leads to weight loss.”

In the above example, there is no support for the claim that running helps you lose weight. The conclusion is already assumed in the premises.

The above is a more extreme example but it basically occurs when the facts that are used as support already assume that the conclusion is true.

Dr A says: “the studies must have been faulty because the vaccine is worthless.

Dr A is out to prove that the studies proving that the vaccine might have some value must be wrong because the vaccines does not have any value.

That is essentially the pattern we are looking for.

(B) There is support offered in the argument pattern in B. Because the author doesn’t trust Jerrold Jersey’s milk recommendations, the author won’t buy the milk.

This is a separate logical fallacy in which you dismiss someone’s argument because of something personal about the author: not on the basis of the facts presented.

It does not fallow the same pattern.

(C) “Wingzz tennis balls perform the best because they are far more effective than any other.”

Just as Dr. A did in his argument, this author is already assuming the Conclusion within the premises.

Effectively, because the balls are the most effective ———-> they are better than any other ball.

There is a slim opening to say “what does effective really mean.” Maybe the ball’s effectiveness is some kind of industry jargon that somehow indicates the balls are better and it can be relied on as actual evidence.

However, common sense would tell us that the author is basically repeating the conclusion in his premises, just as Dr A did in the passage.

I believe this answer best illustrates the “Begging the Question” fallacy.

Posted from my mobile device

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