The gu, the hu, and the jue are types of bronze libation vessels that

Question

The  gu , the  hu , and the  jue  are types of bronze libation vessels that were produced in China during the Shang dynasty, almost 4,000 years ago. Close examination of authentic  gu ,  hu , and  jue  vessels reveals that they all bear incised patterns symbolizing the  taotie , a mythological beast of greed. It must be true then that any bronze libation vessel that does not bear incised patterns symbolizing the  taotie  is not an authentic vessel produced in China during the Shang dynasty.

The argument makes which one of the following errors of reasoning?

(A) basing a generalization on claims that contradict each other

(B) basing a generalization on examples that the argument itself admits are atypical

(C) treating the fact that some members of a given category possess a certain characteristic as sufficient evidence that other objects that possess the characteristic are also members of that category

(D) treating the fact that some members of a category possess a certain characteristic as sufficient evidence that possession of the characteristic is necessary for membership in that category

(E) treating the facts that certain specific objects belong to a given category and that some other objects belonging to that category possess a certain characteristic as sufficient evidence that the former objects also possess that characteristic

MartyMurray · Answer

The  gu , the  hu , and the  jue  are types of bronze libation vessels that were produced in China during the Shang dynasty, almost 4,000 years ago. Close examination of authentic  gu ,  hu , and  jue  vessels reveals that they all bear incised patterns symbolizing the  taotie , a mythological beast of greed. It must be true then that any bronze libation vessel that does not bear incised patterns symbolizing the  taotie  is not an authentic vessel produced in China during the Shang dynasty.

This is a Logical Flaw question. So, key to getting it correct will be to note the conclusion of the argument and how the argument works.

Conclusion:

It must be true then that any bronze libation vessel that does not bear incised patterns symbolizing the  taotie  is not an authentic vessel produced in China during the Shang dynasty.

Support for the conclusion:

Close examination of authentic  gu ,  hu , and  jue  vessels reveals that they all bear incised patterns symbolizing the  taotie , a mythological beast of greed.

We see that the argument works by using information about three types of vessels, "they all bear incised patterns symbolizing the  taotie ," to support a conclusion about "any bronze libation vessel that does not bear incised patterns symbolizing the  taotie ."

What may jump out at us is that it doesn't quite make sense to conclude on the basis of the evidence provided that any bronze libation vessel that does not bear those incised patterns is not an authentic vessel produced in China during the Shang dynasty. After all, the fact that three types of vessel always have such patterns doesn't necessarily mean that all vessels produced in China at that time did.

The argument makes which one of the following errors of reasoning?

The correct answer will accurately describe a flaw in the reasoning of the argument.

(A) basing a generalization on claims that contradict each other

The conclusion of the argument is indeed a "generalization" about "any bronze libation vessel" that does not bear certain patterns.

At the same time, there are no "claims that contradict each other" in the argument.

Eliminate.

(B) basing a generalization on examples that the argument itself admits are atypical

The conclusion of the argument is indeed a "generalization" about "any bronze libation vessel" that does not bear certain patterns.

At the same time, the argument does not admit that the examples of authentic  gu ,  hu , and  jue  vessels it uses are "atypical," meaning not usual.

Rather, it indicates that those examples are typical, when it says that "they ALL bear incised patterns symbolizing the  taotie ."

Eliminate.

(C) treating the fact that some members of a given category possess a certain characteristic as sufficient evidence that other objects that possess the characteristic are also members of that category

This choice is incorrect because what it says is basically the opposite of what the argument does.

After all, the point of the argument is not that "objects that possess the characteristic" "bear incised patterns symbolizing the  taotie " ARE members of the category "authentic vessel produced in China during the Shang dynasty."

Rather, the point is that vessels that do not have that characteristic are NOT members of that category.

Eliminate.

(D) treating the fact that some members of a category possess a certain characteristic as sufficient evidence that possession of the characteristic is necessary for membership in that category

The argument does indeed work by "treating the fact that some members of a category,"  gu ,  hu , and  jue  vessels, "possess a certain characteristic," incised patterns, as evidence that possession of that characteristic is necessary for membership in the category "authentic vessel produced in China during the Shang dynasty."

After all, in concluding that vessels that do not possess those patterns must not be in that category, the argument implies that possessing those characteristics is necessary for being in that category.

Also, that the argument works in that way is a logical flaw because the fact that some vessels produced in China at that time have those patterns doesn't mean that all vessels produced in China did. So, it's not really logical to say that any vessel without those patterns must not be "an authentic vessel produced in China during the Shang dynasty."

So, this choice accurately describes how the argument is flawed.

Keep.

(E) treating the facts that certain specific objects belong to a given category and that some other objects belonging to that category possess a certain characteristic as sufficient evidence that the former objects also possess that characteristic

The argument does not work by using the fact that  gu ,  hu , and  jue  vessels possess the characteristic "bear incised patterns symbolizing the  taotie " to support a conclusion that other objects, other vessels, "also possess that characteristic."

Rather, the conclusion is about other vessels that do  not  possess that characteristic.

Eliminate.

Correct answer:   D

guddo · Answer

The  gu , the  hu , and the  jue  are types of bronze libation vessels that were produced in China during the Shang dynasty, almost 4,000 years ago. Close examination of authentic  gu ,  hu , and  jue  vessels reveals that they all bear incised patterns symbolizing the  taotie , a mythological beast of greed. It must be true then that any bronze libation vessel that does not bear incised patterns symbolizing the  taotie  is not an authentic vessel produced in China during the Shang dynasty.

The argument makes which one of the following errors of reasoning?

The argument shows that authentic gu, hu, and jue vessels have taotie patterns. But then it concludes that any authentic Shang bronze libation vessel must have such patterns.  The mistake  is treating a feature found in some examples of a category as  necessary for the whole category .

(A) basing a generalization on claims that contradict each other

Wrong. The claims do not contradict each other.

(B) basing a generalization on examples that the argument itself admits are atypical

Wrong. The argument does not say gu, hu, and jue vessels are atypical.

(C) treating the fact that some members of a given category possess a certain characteristic as sufficient evidence that other objects that possess the 
characteristic are also members of that category

Wrong. This describes the reverse error. The argument is not saying that vessels with taotie patterns must be authentic Shang vessels.

(D) treating the fact that some members of a category possess a certain characteristic as sufficient evidence that possession of the characteristic is necessary for membership in that category

Correct. The argument sees that some authentic Shang vessels have taotie patterns and wrongly concludes that all authentic Shang bronze libation vessels must have that feature.

(E) treating the facts that certain specific objects belong to a given category and that some other objects belonging to that category possess a certain characteristic as sufficient evidence that the former objects also possess that characteristic

Wrong. The argument is not comparing two separate groups within the category in that way.

Answer: (D)

yc168 · Answer

OE for reference:

Overview:  The argument's conclusion is given in the last sentence: bronze libation vessels lacking the taotie pattern are not authentic vessels produced during China's Shang dynasty. This conclusion is inferred from the claim that all gu, hu, and jue vessels are from the Shang era together with the claim that all gu, hu, and jue vessels bear the taotie pattern.

But note that although the passage states that the gu, the hu, and the jue are types of authentic Shang-era bronze libation vessels, it does not say that these are the  only  types of authentic Shang-era vessels. For all we have been told, there might be dozens of other types of authentic Shang-era vessels. And it could well be that some, or even all, of these other types of Shang-era vessels do not have the taotie pattern. So we cannot reasonably conclude, just from the fact that all gu, hu, and jue vessels have the taotie pattern, that all vessels without that pattern are not authentic Shang-era bronze libation vessels.

The Correct Answer: 
 
D  The argument deals with a category—authentic Shang-era bronze vessels—and claims that some members of that category—the gu, hu, and jue vessels—possess a certain characteristic: they bear the taotie pattern. The argument concludes from this that, for a bronze libation vessel to be an authentic Shang-era vessel, it must bear that pattern. But it is an error to draw that conclusion. It is an error because it is possible, judging only from the information given, for there to be authentic Shang-era bronze libation vessels—those that are neither gu, hu, nor jue—that do not bear the taotie pattern. Answer choice (D) is a description, in general terms, of the error of reasoning the argument makes.

The Incorrect Answer Choices:

A  The argument does not present any claims that contradict each other, so it cannot base any generalization on such mutually contradictory claims. Thus, (A) cannot be a correct description of an error of reasoning that the argument makes.

B  The argument's conclusion is a generalization to the effect that all authentic Shang-era bronze libation vessels bear the taotie pattern. And this generalization is based on examples—the gu, hu, and jue vessels—which may, for all we know, be atypical. But the argument itself says nothing about these vessels being atypical. Thus, there is no indication that the argument is basing a generalization on examples that are admitted to be atypical.

C  If the argument had proceeded along the lines of (C), it would have gone as follows: the fact that some authentic Shang-era vessels—the gu, hu, and jue ones—possess the characteristic of bearing the taotie pattern is sufficient evidence that other Shang-era vessels bearing that pattern are also authentic. So if the argument had gone like this, its conclusion would have been that other Shang-era vessels bearing the taotie pattern are authentic. But this is not what the argument concludes. So (C) cannot be a correct description of an error of reasoning that the argument makes.

E  (E) says that the argument concludes that certain specific objects belonging to a given category have a certain characteristic on the grounds that some other objects belonging to that category have the characteristic in question. But the argument does not draw a conclusion about specific objects; it draws a conclusion about  any  bronze libation vessel that lacks the taotie pattern, even one that has not yet been discovered. So (E) cannot be a correct description of an error of reasoning that the argument makes.

The gu, the hu, and the jue are types of bronze libation vessels that

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GMAT Critical Reasoning (CR) Questions

The gu, the hu, and the jue are types of bronze libation vessels that

Prep Toolkit

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

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From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards