A wave of incidents of unusual violence, from murder to acts of self-d

Question

A wave of incidents of unusual violence, from murder to acts of self-destruction, plagued the small medieval town for a period of five years, nearly wiping out the population. At the same time, there was an unusual shift in the area's weather pattern. Rainfall was so heavy and continuous that the wheat crop probably fell prey to the ergot fungus. When eaten, grain thus affected can cause ergotism, a disease associated with hallucinations and other disturbing psychological side effects. In the end we can conclude that the violence was the result of freakish weather conditions.

Which of the following is the most effective rebuttal to the contention made above?

(A)It is based upon a series of plausible suppositions rather than upon contemporary evidence.

(B) No clear distinction is drawn between cause and effect.

(C)Explanations of historical events cannot be convincing when too great a role is assigned to chance or the irrational.

(D)The author makes no distinction between probable occurrence and actual occurrence.

(E) Such crucial terms as "unusual violence" are not adequately defined in regard to the specific historical event.

CrackverbalGMAT · Accepted Answer

Pre-thinking:

Conclusion:  The violence in the medieval village was the result of freakish weather conditions.

Premises on which the conclusion is based:

i) The period of violence coincided with heavy rainfall in the area.
ii) Wheat crop  could  have been infected with ergot fungus.
iii) Eating ergot infected wheat  could  cause hallucinations or have other psychological side effects.

On first reading, the big problem that first jumps out are the two "could"s that are in the premises on which the conclusion is based. The wheat crop  could  have been infected - however, it is possible that such infection did not happen. Similarly, eating such infected wheat  could  cause hallucinations - then again, it is possible that the infected wheat crop did not produce any such effects.

The premises do not specify how probable the two "could"s are. Basis this thinking, let us assess the options.

(A)It is based upon a series of plausible suppositions rather than upon contemporary evidence.  This is an attractive option at first glance. It is true that the reasoning is based on some suppositions (assumptions, for eg, that the crop  was  infected and the infected wheat  did cause  hallucinations etc.). My problem is with the second part of this option - "rather than contemporary evidence".

In this context, I take "contemporary" to mean "occurring at the same time" or "contemporaneous", rather than belonging to the present time. I do this because this makes the option harder to rule out, since it is not necessary to use evidence from the present to arrive at this conclusion - we could also use evidence from the past. However, a reading of the passage makes it clear that contemporary evidence  has been  used. For instance, data about historical rainfall appears to have been used - clearly evidence from the period in question.

Therefore, not using contemporary evidence is not a criticism that can be leveled at this argument. However, at this point, we can hold on to this option.

(B) No clear distinction is drawn between cause and effect.  Incorrect. The final statement makes it clear that causes and effect are clearly distinguished.

(C)Explanations of historical events cannot be convincing when too great a role is assigned to chance or the irrational.  Again, an interesting option at first glance. However, this appears to be a very sweeping, generalized comment. Can we be sure that  no  historical events can be explained in a way that allows for chance to play a role? Unlikely to be the correct answer.

(D)The author makes no distinction between probable occurrence and actual occurrence.  This appears to be the best option till now. The author does appear to have considered "probable" events (such as the infection and the hallucinations) to have "actually occurred".

(E) Such crucial terms as "unusual violence" are not adequately defined in regard to the specific historical event.  Incorrect. Since the thrust of the argument is on the cause of the violence, we do not require a precise definition of the effect ie; "unusual violence", in order to make an argument about its probable reasons. Additionally, the result of the violence has been reasonably established - "nearly wiping out the population".

Hope this helps.

Akash720 · Answer

IMO A is right.

The author concluded that violence was the result of freakish weather conditions using the above mentioned series of suppositions, without any evidence. Hence A is most debatable option.

StudiosTom · Answer

It is given that that it is probable,but nothing is mentioned about what happened actually.Highlighed the portion that maybe useful to arrive at D.

arvind910619 · Answer

Imo D

The the conclusion is based upon consequences of some probable event. So to undermine the this argument we have to show that the probable event did not occur or some other event occurred.
D questions that the there not certainty that such an even might have occurred and thus this choice undermine the contention.

Siddhuftr · Answer

In my opinion B , 
A says contemporary( present time) evidence ...doesn't make much sense here

Gemelo90 · Answer

B for me as well. Author is mixing between cause and effect.

gvij2017 · Answer

Here two incidents are given..
1. Unusual violence in five years...
2. In same five year, weather pattern disturbance.

Conclusion.
1 leads to 2

B correctly address the concern in stimulus as author has not clearly mentioned cause and effect. These two events can be correlated.

US09 · Answer

IMO D.

The author says that the consumption of the infected grain CAN cause ergotism, but did it really cause and if it did then what proportion of the population was effected-no information is given on these points. Hence, in the absence of the said information, one can only conclude that the consumption of the infected grain MIGHT have been the reason for violence.

Aditi23 · Answer

Please help me understand difference b/w options A and D?

(A)Author's assumption is based on "plausible suppositions" rather than " contemporary evidence ".
(D)The author assumption makes no distinction between "probable occurrence" and " actual occurrence ".
How is "not giving actual occurrence" diff. from "not having actual evidence"??

goforgmat · Answer

If you see (A) says the assumption should be made on contemporary evidence i.e., evidence from the current period.
(D) on the other hand says the assumption should have been based on the actual occurrence which the author doesn't talk about.

(A) is wrong for that reason.Hope its clear.

Aditi23 · Answer

As per google "contemporary" is an adjective. Meaning :
 1.living or occurring at the same time. 
2. belonging to or occurring in the present.
Example: "the event was recorded by a contemporary historian"
Accordingly, A states "Author's assumption is based on plausible suppositions rather than evidences of past (when the event occured) time." Is my understand for use of "contemporary" incorrect. Please Help.

jackspire · Answer

Hello  Bunuel ,

How can we eliminate option B.
As per my understanding there is no clear cut relation mentioned for cause and effect.
So, if someone argues on the point, then the conclusion falls apart.

gvij2017 · Answer

Please explain why it is not B. 
Here two correlated events are mentioned in same time duration. I agree that D is equally correct but not getting why B is incorrect.

Bunuel · Answer

KAPLAN OFFICIAL EXPLANATION

This passage tells a story similar to the anonymous fable of the poison grain, in which all of a kingdom's grain crop is mysteriously poisoned, causing anyone who ate it to go insane. The author describes a wave of unusual violence that swept over a medieval town for a period of five years, characterized by acts ranging from self-destruction to murder. That's followed by a description of a chain of events, beginning with an unusual shift in weather patterns that coincided with the violent period. Due to unusually heavy rainfall, the wheat crop probably fell prey to the ergot fungus, which can cause ergotism, a disease characterized by hallucinations and other psychological abnormalities. The author then concludes that the violence was caused by ("was the result of") the freakish weather conditions. There's the element of causation alluded to above.

An 800 test taker recognizes causation in all of the various ways in which it is suggested by the wording of arguments.

When presented with a causal argument—especially when looking for a rebuttal that argument— the first thing to do is check to see that the causal mechanism described is appropriate. The author blames the unusual acts of violence in the town on ergot fungus. However, he doesn't know for a fact that the ergot fungus was present in the town's wheat. He knows conditions were ripe for the formation of the fungus (i.e., lots of rain), and he knows fungus-infected wheat can cause psychological disturbances—but the crucial point, the actual presence of the fungus, is mere supposition. (Note how the author says that the wheat crop "probably" fell prey to the fungus.) As (D) points out, the conclusion treats the probable occurrence of the fungus as if it were a certain, actual occurrence. And therein lies the scope shift as well; the author argues from probability in the evidence to a clear-cut, definite statement of actual causation in the conclusion. In arguing against this reasoning, it would be perfectly appropriate to point out that the author misses the distinction described in  (D), the correct answer.

(A) Contrary to (A), the argument does use contemporary evidence: the shift in the area's weather patterns at the time of the incidents of violence.

(B) Actually, the author does set up a clear chain of cause and effect—rain causes fungus which causes psychological abnormality. The causes and effects are perfectly distinct; the question is whether the causal mechanism described is valid.

(С) distorts the argument, since no role at all is assigned to the chance or irrational in causing the psychological disturbances.

(E) The term "unusual violence" is reasonably well defined as involving acts of murder and self-destruction so pervasive as to endanger the town's very survival. We really can't ask for a more comprehensive definition than that.

Ilanchezhiyan · Answer

IMO A
the author has not provided evidence that people had ergotism; 
Passage mentions no evidence to support his claims.

A_Nishith · Answer

Breakdown of the Argument: 
The argument suggests that unusual weather conditions, particularly heavy rainfall, led to the growth of ergot fungus on wheat. When consumed, this fungus can cause ergotism, a disease known for causing hallucinations and psychological disturbances, which are linked to violent behavior. Based on this chain of events, the argument concludes that the weather caused the unusual wave of violence in the town.

Question Focus:
We are tasked with finding the most effective rebuttal to this argument. The chosen answer, D, states: "The author makes no distinction between probable occurrence and actual occurrence."

Evaluating the Answer Choices:
(A) It is based upon a series of plausible suppositions rather than upon contemporary evidence.

This choice argues that the conclusion is built on assumptions without direct evidence. While it questions the argument's speculative nature, it doesn't specifically address whether the scenario actually occurred or just likely happened. Hence, it is a weaker rebuttal than D.

(B) No clear distinction is drawn between cause and effect.

This choice would be effective if the argument confused what caused what, but the argument explicitly claims that weather caused the fungus, which in turn caused the violence. So this rebuttal does not directly weaken the argument’s structure, as there is a clear cause-and-effect chain proposed.

(C) Explanations of historical events cannot be convincing when too great a role is assigned to chance or the irrational.

This is more of a general critique of using irrational explanations for history. While it raises doubt, it doesn't address the argument's failure to separate what might have happened from what actually happened, as D does.

(D) The author makes no distinction between probable occurrence and actual occurrence.

This is the strongest rebuttal because the argument assumes that the chain of events actually occurred based on circumstantial evidence. The argument speculates that the heavy rain caused the ergot fungus, and that the violence was due to ergotism. However, there is no clear evidence that:
The wheat was definitely infected by ergot fungus.
The townspeople definitely consumed the contaminated wheat.
The violence was directly caused by ergotism, rather than other factors.
This rebuttal points out that the argument does not distinguish between what was likely or probable (freakish weather causing ergot fungus, leading to violence) and what actually occurred. This distinction is crucial because without firm evidence, the conclusion is merely speculative.

(E) Such crucial terms as "unusual violence" are not adequately defined in regard to the specific historical event.

This choice argues that the term "unusual violence" is vague, but this doesn't directly undermine the logical chain of events in the argument. It’s a weaker rebuttal compared to D, which points out the lack of a distinction between likelihood and actuality.

Conclusion: 
(D) The author makes no distinction between probable occurrence and actual occurrence is the most effective rebuttal because it points out that the argument is speculative, based on what probably happened rather than providing direct evidence of what actually happened.

Answer: D

NPProb · Answer

I’m sorry, but the word “contemporary” in choice A means “the same time period as the events” in chatGPT’s opinion:
 
There is an important sentence in the logical chain of this question:
 
which is a plausible supposition without contemporary evidence, which means A is the right one.
But anyway, I think this question is very controversial, poor-quality.

A wave of incidents of unusual violence, from murder to acts of self-d

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A wave of incidents of unusual violence, from murder to acts of self-d

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