Dobson: Some historians claim that the people who built a ring of ston

Question

Dobson: Some historians claim that the people who built a ring of stones thousands of years ago in Britain were knowledgeable about celestial events. The ground for this claim is that two of the stones determine a line pointing directly to the position of the sun at sunrise at the spring equinox. There are many stones in the ring, however, so the chance that one pair will point in a celestially significant direction is large. Therefore, the people who built the ring were not knowledgeable about celestial events.

Which one of the following is an error of reasoning in Dobson’s argument?

(A) The failure of cited evidence to establish a statement is taken as evidence that that statement is false.

(B) Dobson’s conclusion logically contradicts some of the evidence presented in support of it.

(C) Statements that absolutely establish Dobson’s conclusion are treated as if they merely give some support to that conclusion.

(D) Something that is merely a matter of opinion is treated as if it were subject to verification as a matter of fact.

(E) Dobson’s drawing the conclusion relies on interpreting a key term in two different ways.

nightblade354 · Accepted Answer

Dobson: Some historians claim that the people who built a ring of stones thousands of years ago in Britain were knowledgeable about celestial events. The ground for this claim is that two of the stones determine a line pointing directly to the position of the sun at sunrise at the spring equinox. There are many stones in the ring, however, so the chance that one pair will point in a celestially significant direction is large. Therefore, the people who built the ring were not knowledgeable about celestial events.

Context: Some historians claim that the people who built a ring of stones thousands of years ago in Britain were knowledgeable about celestial events. The ground for this claim is that two of the stones determine a line pointing directly to the position of the sun at sunrise at the spring equinox

Premise: There are many stones in the ring, however

Conclusion: so the chance that one pair will point in a celestially significant direction is large. Therefore, the people who built the ring were not knowledgeable about celestial events

OK, so we are told about a theory where certain objects helped people, potentially, a while ago spot items in the sky. But our argument is that there are a bunch of these items, so the fact that there are so many probably means it was an accident. Hmm. So we are saying that, in our opinion, that if you something could be a coincidence, not purposeful, that that destroys the argument. But this doesn't destroy our argument because it is simply our opinion. Let's hope something matches this.

Which one of the following is an error of reasoning in Dobson’s argument?

(A) The failure of cited evidence to establish a statement is taken as evidence that that statement is false --  Let's break this sentence down: The failure of cited evidence (the rings) to establish a statement (that they point to sky items on purpose) is taken as evidence that that statement is false (They are not experts). Hmm. Pretty good. We are told something is a fallacy because the evidence presented doesn't add up. But this is just one example. Can we conclude that there weren't other structures? Further, can we see how the structure matches well with what the actual argument did? We are told that the author doesn't believe it because of coincidence. No additional evidence is given. He is just restating his opinion. So looking at the answer choice, because we have no other evidence and we disagree with it, we assume that the statement is false. Perfect. 
 
(B) Dobson’s conclusion logically contradicts some of the evidence presented in support of it --  Our premise matches our conclusion pretty well. This would be like saying I hate red items. And all apples are red. Therefore, I love apples. Wrong error.

(C) Statements that absolutely establish Dobson’s conclusion are treated as if they merely give some support to that conclusion --  This is the opposite, in a way. This is saying that the question doesn't believe the arguer's statement. But it is the other way around.

(D) Something that is merely a matter of opinion is treated as if it were subject to verification as a matter of fact --  Trap answer choice. This is saying that the view about the rings is being treated as a matter of fact when it is opinion. It is established that this is fact and we are arguing against it. The error is not giving too much credit to the claim we are disproving. The issue is in our argument, which is an opinion itself. This is why this is a tricky answer choice. You see the word "opinion" and you jump on it. But we need to break down what the statements are actually saying before we can make a judgement call about it being the correct answer. In this case, this is 100% wrong.

(E) Dobson’s drawing the conclusion relies on interpreting a key term in two different ways --  No terms conflict. If we used "knowledgeable" or "rings" in different ways this would be the case, but we do not do this.

gmatavenue · Answer

OFFICIAL EXPLANATION

(A)

The claim that Dobson tries to rebut—that the ancient builders of this ring of stones must have known about celestial events—is based on the provocative fact that a line drawn between two of the stones points to a significant phenomenon in the sky. Phooey, says Dobson—there are many stones in the ring, so many that the odds of any two pointing in a provocative way are huge. But not content to leave well enough alone, Dobson announces that he has proved that the ancients didn’t know about celestial events. Whoa! Maybe the evidence for the original claim is skimpy, but Dobson goes too far in claiming that that skimpiness proves the claim false. That’s what (A) is getting at. Let’s try an analogy—a parallel argument, as it were. Suppose you argue that the players on the Columbus Kings football team must be churchgoers, because every Sunday I see some of them walking toward a church. Well, in response, I could argue that that evidence is insufficient, that it doesn’t prove your point, that any of them could be seen walking towards some house of worship; but I cannot say that I have therefore proved that the players aren’t churchgoers!

This is essentially the same error that the stimulus author commits.

(B) Dobson’s evidence contradicts the original claim. That’s what a rebuttal does. But he doesn’t contradict himself.

(C) As described above, the evidence falls far short of “absolutely establishing” Dobson’s conclusion.

(D) Whether the ancients knew about celestial events is a question subject to factual verification and not a matter of opinion. Of course, the right kind of evidence must be assembled, which is why (A) is correct. But it is a fact-based dispute.

(E) Dobson equivocates on no term, key or otherwise (“equivocation” means using the same word in two different meanings or senses). He changes no meanings en route.

• Pre-phrase an answer to each Logical Flaw question, and try hard to find a choice that matches your pre-phrasing. Without pre-phrasing, you can waste an awful lot of time browsing among the choices.

tryingharder · Answer

A it is

Statement:  Some historians claim that the people who built a ring of stones thousands of years ago in Britain were knowledgeable about celestial events. 
 Evidence:   The ground for this claim  is that two of the stones determine a line pointing directly to the position of the sun at sunrise at the spring equinox. There are many stones in the ring,  however,  so the chance that one pair will point in a celestially significant direction is large. 
 Statement:  Therefore, the people who built the ring were not knowledgeable about celestial events.
Which one of the following is an error of reasoning in Dobson’s argument?
(A) The failure of cited evidence to establish a statement is taken as evidence that that statement is false>> CORRECT 
(B) Dobson’s conclusion logically contradicts some of the evidence presented in support of it.>> thought that this one is close, but..the conclusion in the argumnt is strongly suported by the premise(evidence).  
(C) Statements that absolutely establish Dobson’s conclusion are treated as if they merely give some support to that conclusion>> OOS 
(D) Something that is merely a matter of opinion is treated as if it were subject to verification as a matter of fact>> OOS 
(E) Dobson’s drawing the conclusion relies on interpreting a key term in two different ways>> just 1n only way. no 2 ways

nusmavrik · Answer

Conclusion : is based upon the "chance that " ---> this is NOT a proof. Hence its failing to ESTABLISH a statement. the people "were not knowledgeable about celestial events."

A it is.

E : interpreting a key term ----> If this is referring to "pair of stones". In both instances the pair points in the significant direction. Interpretation was not done in different way - just one way.

cano · Answer

A is the answer.
Dobson's problem is that he fails to make a statement.
The statement should be something like: the pair of stones doesn't point in a celestially significant direction.
The way he put it is just a doubt. If his conclusion was this one instead: "there is a large chance that the people who build the ring were not knowledgeable about celestial events", then his reasoning would be correct. So he didn't make a statement yet, but he brings up a strong conclusion, so the problem is either his reasoning or his conclusion. Since this exercise counts on Dobson keeping his conclusion unchanged, then the problem is his reasoning.

greatman1234 · Answer

I will go with A

B out of scope
C weak or general statement but a close call
D trap with intricate language.
E key term?? OOS

fluke · Answer

Good one!!!

"A"
Dobson conclusion is flawed because it concluded the theory WRONG just because the reasoning used in support of the historians' claim was flawed or inept.

I was stuck because I thought "A" was mere a method of reasoning, and not the reasoning error and then I saw "statement is FALSE". The claim by historians may not be false, Dobson, the reasoning used to support historians' claim was false.

sharathnair14 · Answer

nightblade354  
 
In Option C, 
"the statement that establishes the conclusion" =?
and 
treated as if "they merely support the conclusion" =?

What are these two phrases in your opinion wrt to the argument?

Is it referring to the probability of stones aligning a certain way to point at the sun? Just want to confirm.

nightblade354 · Answer

Yes, the first statement are the observations, and the second would be his overall conclusion.

riri3026 · Answer

Can someone help me out?

I chose D, obvious trap answer after reading why I am wrong. But what i am not understanding is what does option A even mean?

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Dobson: Some historians claim that the people who built a ring of ston

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Dobson: Some historians claim that the people who built a ring of ston

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