Anthropologist: After mapping the complete dominance hierarchy for a troupe of vervet monkeys by examining their pairwise interaction, we successfully predicted more complex forms of their group behavior by assuming that each monkey had knowledge of the complete hierarchy. Since our prediction was so accurate, it follows that the assumption we used to reach it was in fact true.

Primatologist: Although I agree that your assumption helped you make those predictions, your conclusion does not follow. You might as well argue that since we can predict the output of some bank cash machines by assuming that these machines actually want to satisfy the customers’ requests, these cash machines must really have desires.

Speaker 1 Summary
The anthropologist claims that an assumption about vervet monkeys’ knowledge of the hierarchy within their troupe has been proven true. How so? Because this assumption led to accurate predictions of the monkeys’ group behavior.

Speaker 2 Summary
The primatologist believes that the anthropologist’s predictions do not provide sufficient support to conclude that the anthropologist’s assumption is true. This is supported by an example: assuming that an ATM wants to help customers can lead to accurate predictions of the ATM’s outputs, but that doesn’t mean the ATM actually has desires.

Objective
We need to find a point of disagreement. The key disagreement is about whether the anthropologist’s predictions are sufficient support for the conclusion that the assumption about monkey knowledge is true.

A
whether the anthropologist successfully predicted the behavior of individual monkeys by use of the map of the troupe’s dominance hierarchy
The speakers agree about this point. The anthropologist claims that these successful predictions happened, and the primatologist accepts that the anthropologist was able to predict the monkeys’ behaviour.
B
whether the output of a bank cash machine can be accurately predicted on the basis of knowledge of the requests made to it by customers
The primatologist believes that such a prediction is possible. The anthropologist, on the other hand, never says anything about cash machines. There’s certainly no indication that the anthropologist disagrees with the primatologist on this point.
C
whether vervet monkeys can have knowledge of the complete hierarchy of dominance relations that exists within their own troupe
The anthropologist believes that vervet monkeys can have this knowledge. In fact, it’s a necessary assumption for the conclusion drawn. The primatologist offers no opinion; the disagreement is about having grounds to believe a claim, not whether the claim is actually true.
D
whether the fact that the anthropologist’s assumption led to such successful predictions provides sufficient grounds for the claim that the vervet monkeys had knowledge of their dominance hierarchy
The anthropologist thinks that the predictions are sufficient grounds—that’s the anthropologist’s entire argument. The primatologist thinks that the predictions are insufficient and that the anthropologist’s conclusion “does not follow.” This is the point of disagreement.
E
whether the behavior exhibited by vervet monkeys in experimental situations can be used as the basis for a generalization concerning all vervet monkeys
Neither speaker says anything about generalizing vervet monkeys’ behaviour in experimental situations to apply to all vervet monkeys. This simply isn’t discussed.

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Marion knows that the bridge on her usual route is closed and that, unless she takes the train instead of driving, she can get to work on time only by leaving at least 45 minutes early. She must go to her neighborhood bank before leaving for work, however, and the bank will not be open in time for her to do so if she leaves 45 minutes early. Therefore, since she hates taking the train, Marion cannot avoid being late for work.

Summarize Argument
The author concludes that Marion can’t avoid being late for work. He supports this with four premises:

(1) Marion hates taking the train.

(2) If she doesn’t take the train, she must leave 45 minutes early to be on time for work.

(3) If she leaves 45 minutes early, her bank won’t be open yet.

(4) She must stop at her bank before leaving for work (so she can’t leave 45 minutes early).

Identify and Describe Flaw
The author never establishes that Marion will drive to work. Instead, he assumes that Marion won't take the train simply because she hates it, without providing any other evidence. Marion could still take the train, even if she dislikes it, and she might then have enough time to visit the bank and be on time for work.

A
mistakes a situation that almost certainly affects many people for one that affects a particular person alone
The bridge closure may affect many people, but the author’s conclusion is based on premises about Marion’s schedule and needs. He’s not mistaking a situation that affects many people for one that affects Marion alone because he’s only addressing Marion’s particular situation.
B
ignores the fact that people often know that something is the case without considering all the consequences that follow from its being the case
This doesn’t point out the assumption that, just because Marion hates the train, she won’t take the train. Also, the argument is only about whether Marion will be late for work; the author doesn’t need to consider all the consequences of her being late.
C
assumes without justification that because people generally have an interest in avoiding a given result, any particular person will have an interest in avoiding that result
This is the cookie-cutter “whole-to-part” flaw. But like (A), the author’s conclusion is based on premises about Marion’s schedule and needs, not on premises about people in general.
D
treats evidence that someone will adopt a particular course of action as though that evidence excluded the possibility of an alternative course of action
Marion hates the train. The author takes this evidence to mean that she won’t take the train and will drive instead. He mistakenly uses this to exclude the alternative possibility that she might still take the train, despite hating it.
E
overlooks the possibility that someone might occasionally adopt a given course of action without having a good reason for doing so
The author isn’t assuming that Marion won’t take the train because she doesn’t have a good reason for doing it. Instead, he’s assuming that Marion won’t take the train because she hates taking the train.

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This is a must be true question, as it asks: If the statements above are true, which one of the following must also be true on the basis of them?

This stimulus is full of conditionals with comparisons. The first sentence and the second half of the second sentence both begin with the conditional indicator “when”, which gives us three conditionals in addition to the “but if” beginning the second sentence. All three conditionals involve comparisons indicated by “than” or “as”. If we notice that the “fall more slowly” of the necessary condition of the first conditional is equivalent to the “fall less rapidly” of the second conditional, and that the “unable to lower prices” of the second conditional is equivalent to the “cannot lower prices” of the third, we should recognize that the three conditionals form a chain: slower adoption → slower falling costs → cannot lower prices → squeezed out. The contrapositive of this chain is: not squeezed out → can lower prices → not slower falling costs → not slower adoption. Since this is a must be true question with a chain of conditionals, we should be looking for answers which say something about a condition earlier in this chain or the contrapositive chain that guarantee a condition further down the chain. Let’s see if any answers take this form:

Answer Choice (A) We are told nothing about raising prices, only stuff about being unable to lower them.

Answer Choice (B) This answer is a classic case of confusing sufficiency for necessity. Just because foreign competitors (FCs) adopting technologies faster is sufficient to squeeze a country out of the global market, doesn’t mean that it is required for a country to be squeezed out of the market.

Answer Choice (C) This answer makes the same mistake as B, just with different parts of our chain of conditionals.

Answer Choice (D) The problem with this answer is that it gives us the negation of the first condition of our conditional chain, because “the same rate” is equivalent to “not slower”, but we can only use the negation in the contrapositive where it is the final necessary condition. Even if A→B is true, we can’t infer anything from B alone. In this case we certainly cannot infer that neither group will be squeezed out of the market. It is entirely consistent with what we are told in the stimulus that there are a million ways a manufacturer can be squeezed out of the market even when it has the same tech adoption rate as its FCs.

Correct Answer Choice (E) Our contrapositive chain comes in handy here. If we look at it, we’ll notice that if a manufacturer can lower prices as rapidly as their foreign competitor, then they must not have slower falling costs, which means that they must not be adopting tech at slower rate. If it is true that a manufacture can lower prices as rapidly as its FCs, then it is required that it is not adopting tech at a slower rate.


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This is a Method of Reasoning question, and we know this because of the question stem: “The argument counters the objection by...”

The author starts out by laying out an objection to making the US school year align with Japanese/European school calendars. This objection to this proposal is that it violates a tradition that was established in the 19th century. The author then says that this objection “misses its mark,” or that their proposed reasoning that not establish support for their objection. This is our author’s main conclusion. His reasoning is that our calendar year aligned to fit harvesting time in rural areas that depended on children working. So, if we’re appealing to tradition, the tradition is actually based on economic needs and that’s what we should look to. The author is saying that the objection mistakes what the purpose of the traditions actually was.

Answer Choice (A) There is no misunderstanding about the amount of time schools have been closed.

Answer Choice (B) The stimulus is not calling into question the relevance of tradition; the author is calling into question their understanding of what said tradition means.

Correct Answer Choice (C) Note that the author’s argument takes issue with the reasoning behind the objection. This explains exactly how the author shows that the opponents of the change are misunderstanding what traditions imply for this social change.

Answer Choice (D) The author does not call into question the opponents’ genuine concern.

Answer Choice (E) The issue here is that the author isn’t saying change should be justified by tradition. If it is, however, the purpose behind the traditions the opponents put forward is not correct.


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