Historian: We must reject the theory that the Library of Alexandria

Question

Historian: We must reject the theory that the Library of Alexandria was destroyed in a wildfire. If it were true that the library burned down, then nearly all the ancient wisdom contained in its scrolls would have been lost forever. That would be an irreplaceable tragedy for human knowledge.

Which of the following best describes the flaw in the historian’s argument?

(A) Assumes that if an event’s occurrence would be historically significant, then evidence of that event must have been preserved and widely known.
(B) Assumes that the destruction of a single building would necessarily be the sole cause of the loss of ancient texts.
(C) Treats the undesirability of an event’s outcome as a reason to believe that the event did not occur.
(D) Presumes, without justification, that the contents of the library were completely unique and existed nowhere else.
(E) Fails to consider the possibility that some scrolls could have survived even if the building itself burned down.

guddo · Answer

C is correct.

The argument rejects the wildfire theory solely because, if true, it would imply a disastrous outcome (an “irreplaceable tragedy”). But an event can be tragic and still have happened. So the historian is using “this would be awful” as a reason to believe “it did not occur,” which is exactly the flaw in (C).

KindFleet · Answer

Hi,
I completely agree with your logic for choosing option: (C) but can you help me know what's wrong in option (B) & (D). I myself choose C only coz that actually relates to the para, but after re-looking the options again, I'm unable to find anything to discard B & D.

commodinostrum · Answer

B and D may seem relevant because they challenge assumptions underlying the premises, but they don't identify the flaw in the argument's reasoning. Even if we grant the premises, the conclusion still doesn't follow: the author provides no evidence for rejecting the theory other than “it would've had disastrous consequences, so it must not have happened.” Remember, this is a flaw question, not a strengthen/weaken question.

Another way to look at it is that we shouldn’t attack every premise, or the criticism would never end. For example, if a scientist draws a conclusion from a study, we don’t automatically call the argument flawed just because the author didn’t fully justify why the study itself is valid.

Reaper795 · Answer

Help me understand the passage please.

To me, when the author says "That would be an irreplaceable tragedy for human knowledge." author is merely stating his opinion and not using it as an evidence for an event, since the said sentence above starts after a full stop.

guddo · Answer

The full stop does not matter. Logical role is determined by how the sentence is used in the argument, not by punctuation.

The structure is:

Premise: If the library burned down, nearly all ancient wisdom would have been lost.
Premise: That loss would be an  irreplaceable tragedy .
Conclusion: Therefore, we must reject the wildfire theory.

So the author is using the tragic result as a reason to reject the theory. That is the flaw: an outcome can be  terrible  and still be true.

If the author only said, “That would be tragic,” without using it to support rejection of the theory, then it would just be commentary. But here it is part of the reasoning.

egmat · Answer

Hi Reaper795,

You're actually half-right, and that half is the key to seeing why  C  is the flaw.

Yes,  "That would be an irreplaceable tragedy for human knowledge"  is  a value judgment - the author's opinion about how bad the outcome would be. You're correct that it isn't hard factual evidence.

But here's the twist:  that opinion is the  only  thing the author gives us to justify the conclusion. Look at what's actually on the page:

-  Conclusion:  "We must reject the theory that the Library was destroyed in a wildfire."
-  Support offered:  if it burned, the wisdom would be lost - and  that would be a tragedy.

There is no evidence about what actually happened - no records, no physical findings, nothing about the fire itself. The author leans entirely on "this would be an awful outcome" to conclude " therefore  it didn't happen."

So the sentence starting after the full stop isn't a harmless aside. It's the  load-bearing reason . That's precisely why  C  nails the flaw: the author  treats the undesirability of the outcome as a reason to believe the event didn't occur.  An event can be tragic and still be true - how bad a consequence would be tells us nothing about whether it happened.

A quick parallel to feel it:

"I refuse to believe I failed the exam. If I failed, I'd have to repeat the whole year - and that would be devastating."

"Devastating" is pure opinion. But notice it's the  only  reason given for "I didn't fail." Wanting something not to be true - or dreading its fallout - doesn't make it false. Same move, same flaw.

So don't discard that sentence as mere opinion - recognize that the author is illegitimately using it  as  the reason. That recognition is exactly what  C  describes.

Answer: C

Historian: We must reject the theory that the Library of Alexandria

Prep Toolkit

Top 5 GMAT Debrief Videos

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

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards

GMAT Critical Reasoning (CR) Questions

Historian: We must reject the theory that the Library of Alexandria

Prep Toolkit

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

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards