PrepTest 108, Section 3, Question 26
Anthropologist: After mapping the complete dominance hierarchy for(104 more words not shown)
Which one of the following(14 more words not shown)
- Awhether the anthropologist(17 more words not shown)
- Bwhether the output(22 more words not shown)
- Cwhether vervet monkeys(16 more words not shown)
- Dwhether the fact(25 more words not shown)
- Ewhether the behavior(20 more words not shown)
Reading the argument
They agree that the prediction worked. They disagree about what that success proves.
The anthropologist mapped the monkeys' relationships by looking at pairs, then used the assumption that each monkey knew the complete hierarchy to predict group behavior. The final claim goes further: because the prediction was accurate, the assumption must have been true.
Think of solving x + 3 = 7. Subtracting 3 gives x = 4. Someone might instead pick 4 because it's their favorite number and happen to land on the correct answer. The result is right, but that doesn't make choosing a favorite number a sound way to solve the equation. Success alone doesn't validate the route taken.
The primatologist makes a related point with the ATM. Imagining that it wants to satisfy customers might help us predict its output, but an accurate prediction wouldn't establish that the machine really has desires. Likewise, the monkey prediction could work without establishing the assumed knowledge.
What we’re looking for
For the disagreement question, keep our prediction narrow: is this success enough to establish that the monkeys knew the hierarchy? The anthropologist says yes. The primatologist says no. Don't turn that objection into a claim that monkeys couldn't possibly know it.
Working the answers
- A
This doesn't identify the objection. The primatologist accepts the role of the assumption in making successful predictions. The passage describes predictions of more complex group behavior, while A mentions individuals; either way, the reply doesn't challenge the success of the prediction. It challenges what can be inferred from that success.
- B
The cash machine appears only in the primatologist's analogy. The anthropologist gives no view about predicting its output, so we cannot assign the speakers opposite positions on this statement. An example used by one speaker is not automatically a point of disagreement.
- C
Could the monkeys have that knowledge? The primatologist leaves that possibility open. Saying “You haven't shown that they know” doesn't mean “They cannot know.”
Both speakers could agree that the knowledge is possible and still disagree about whether this experiment establishes it. C changes a dispute about the evidence into a dispute about the monkeys' abilities.
- DCorrect
This asks whether the accurate prediction provides enough support for the knowledge claim. The anthropologist explicitly says the assumption must be true because the prediction was accurate. The primatologist explicitly denies that the conclusion follows and uses the cash-machine example to show why. We have a clear yes from one speaker and no from the other.
- E
Neither speaker compares experimentally observed monkeys with all vervet monkeys. The primatologist doesn't object that these animals are unusual or that a laboratory changes their behavior. The disagreement concerns the inference from predictive success to knowledge, not whether this group represents the species.
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