#8 - A history book written hundreds of years ago contains

[Administrator]

Complete Question Explanation

Assumption. The correct answer choice is (C)

Scholars believe that because a history book contains several inconsistencies, the book must draw its information from more than one source.

The scholars ignore the possibility that the history book is simply a copy of a previous source that contained inconsistencies.

The conditional wording of this choice is "Conclusion Follows → Choice True," which means that you are supposed to identify a necessary assumption of the argument. Since the scholars ignore a possibility, the correct answer will likely address that possibility.

Answer choice (A): This choice does not clearly address the issue except to make it harder to understand why the inconsistencies exist. If you read into this choice (you should not), you can argue that it makes it likely that if discrepancies make their way through to the final product, it is because the author was overwhelmed, and on that basis you can argue that this choice supports the idea of multiple sources. That argument has limited value. Furthermore, the book could utilize multiple sources even if the author was unaware of the possible discrepancies, so this incorrect choice is unnecessary.

Answer choice (B): Whether or not the average reader would recognize the inconsistencies is irrelevant to the number of sources the history book utilizes.

Answer choice (C): This is the correct answer choice. Since the scholars ignore the possibility, they assume that the history book does not simply copy a source that contained inconsistencies.

Answer choice (D): This choice is vulnerable to the same general critique as is answer choice (A). The fact that this choice is specific to the author in question does not make this choice necessary.

Answer choice (E): If the author of the book was familiar with all available source material, that makes it highly likely that the author drew on multiple sources even unintentionally. However, an author would only have to be familiar with a few sources to utilize multiple sources, so it might be unnecessary that the author was familiar with all the available source material.

[Sdaoud17]

Usually when I have an assumption question , I turn the question to a weaken Question mantel (Using the Negation Method). However with this question I used the Negation method with Answer C which is " the History books author used Source that contained inconsistencies repeated in the history book" when I read it like that , It didnot attack conclusion. Can you explain how ?

Thank you

[Justin Eleff]

Remember that the stimulus is driving at whether a given book's inconsistencies prove that its author consulted more than one source. But (C) raises an interesting possibility, albeit in kind of a sly way: What if the author did consult only one source -- but that source itself contained inconsistencies? Then the author might preserve those inconsistencies by repeating the inconsistent information from the (one and only) source.

So the negated form of answer choice (C) now tells us that a source used by the author was internally inconsistent, and thus gives us a new way of winding up with inconsistencies in the newer book we're talking about. Maybe the author didn't consult multiple sources that weren't all consistent with each other; maybe the author only consulted one source, but it wasn't entirely consistent with itself. If that is in fact what happened, one source alone could explain the new book's inconsistencies. If not, the inconsistencies must have come from multiple sources (or from the author's somehow botching information to create inconsistencies where there weren't any beforehand).

[esolhtalab]

I think I got this question incorrect because I don't entirely understand what the correct answer C is saying. I could use some help negating it and making the connection as to how it destroys the argument.

C. the history book's author used no source that contained inconsistencies repeated in the history book.

[Steve Stein]

Hi,

That's a good question; it's clear that the makers of the test often go out of their way to make statements more challenging to negate. Let's start at the beginning:

The author of the stimulus provides that the book has several inconsistencies, and concludes that the author of the book must have gotten information from more than one source.

When we negate correct answer choice (C), we get something along the following lines:

• "The books author may have used a source that contained inconsistencies which were then repeated in the history book."

If this is the case, then the author would not have needed multiple sources to explain those inconsistencies—they could all have come from a single source.

So, in order to draw the conclusion in the stimulus, the author must be assuming that the history book's author did not use a source that provided those multiple inconsistencies.

I hope that's helpful! Please let me know whether this is clear—thanks!

~Steve

[esolhtalab]

Thank you! This was helpful!

[Etsevdos]

Negating C:

Would this be negated as follows:

The history book's author did not use no source....history book".... double negative = positive; hence: ...author did use a source". When I did this one, had an issue negating it but believe my approach in retrospect is the correct way?

[Francis O'Rourke]

Hi Etsevdos,

That is very close to the logical negation of answer choice (C). I would phrase the logical negation of this statement as "The author may have used a source that contained inconsistencies repeated in the history book."

The difference between our logical negations is a matter of certainty. Since this answer choice states that the author "...used no sources..." we can negate that phrase to yield "...may have used sources..." We are negating a statement that asserted a certain, definite, or guaranteed relationship (Any source used must have contained no inconsistencies), so we should negate the certainty of that statement. Doing so gives us the possibility that the source used was inconsistent, not that it definitely was inconsistent.

[Etsevdos]

Francis - Thanks. So in math terms, it is essentially equivalent to : 100% or not 100%. You cannot say the negative of 100% is zero? Is that analogy the way I should understand this negation? Thanks again.

[nicholaspavic]

Hi etsvdos,

If I can jump in for Steve here, I think you are stating it correctly. So well done and keep up the good work!