Logical Reasoning

PT108 · S3 · Q15 A survey of historians shows

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A survey of historians shows that most believe written texts to be the best source for historical understanding.

Conclusion

These historians neglect many important repositories of historical knowledge.

Evidence

These historians believe that written texts are the best source for historical understanding. They don't regard painting, architecture, music, dance, or culinary arts as the best source.

Evaluate

It looks like the evidence is talking about whether or not historians consider something "the best source" for historical understanding.

But the conclusion is talking about whether or not historians are neglecting an important source of historical understanding.

Since we're being asked what the author assumes (what she takes for granted), they are probably testing this missing link.

Goal

Look for an answer pointing out the move from,

Or we could put that as an objection --

15.

The reasoning in the argument is flawed because the argument takes for granted that

there are no potential sources
Too Strong: no other sources
The author has not committed to the crazy-extreme claim that the only potential sources for historical understanding are 1. written texts 2. the arts If we negated this "assumption", it would be saying "There are potential sources of of historical understanding beyond both written texts and the arts". Would that weaken? No, that would only strengthen the author's argument. The more potential sources are out there, the easier it is for this author to argue that these historians are neglecting some important sources.
5% picked this
painting, architecture, music, dance, and
Too Strong: only
The author never committed to the extreme sounding idea that "the only value that fields like architecture / music / cooking have are as sources of historical understanding." Architecture is only important as a source for historical understanding? Not important as a source of shelter? If we negated this and said that, "arts are important for reasons in addition to being important sources of historical understanding" it wouldn't hurt the argument in any way.
6% picked this
Correct
there are no sources for
Why this is right
I think they want us to go cross-eyed while processing this answer, but we certainly have to consider it, since we were looking for "if not best, then neglect". The syntax of the sentence is "There are no X's that are neither Y nor Z." How can we clean that up? If you need to, think of a real world statement that fits that syntax: "There are no Presidents that are neither former military nor college graduates." This would mean, "every President was either former military, a college graduate, or both." No X is neither Y nor Z = Every X is at least one of those two things. No sources are neither best nor neglected, every source is at least one of those two Every source of historical understanding is either considered best, neglected, or both. Hence, we can derive conditionals like this: if a source isn't the best, it's neglected if a source isn't neglected, it's the best When we know that "at least one of Y and Z is true", then that allows us to write conditionals like "If Y is false, then Z must be true" and "If Z is false, then Y must be true". Phew, still alive? We were looking for this missing link: "if historians don't consider it the best, then they will neglect it" That's what this cruel absurdity of an answer choice gave us. if a source isn't the best, it's neglected
Skill tested: Flaw · how this choice captures the argument's function is the move to repeat next time.
61% picked this
something other than written texts
Bad Conclusion Match
If we negated this, it would be saying "written texts are the best source". That wouldn't weaken the author's argument. The author isn't disagreeing with historians' assessment of the best. He's just assuming that they won't bother consulting sources of info that aren't the best, and in so doing they'll be neglecting important sources like the arts. Our author can agree that written texts are the best, but still think that other sources are important sources, which historians are neglecting.
9% picked this
the other sources for historical
Opposite
The author was assuming that the sources she was naming, such as painting/music/dance, are important repositories of historical knowledge. That's how the author was making her case. Historians don't think these (important repositories) are the best source. Thus, historians are neglecting important repositorites.
20% picked this

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