PrepTest 106, Section 3, Question 22
Researcher: The role of chemicals called pheromones in(73 more words not shown)
The researcher's argument requires the(2 more words not shown)
- Awhatever does not(10 more words not shown)
- Bvoluntary action cannot(4 more words not shown)
- Cfree will can(5 more words not shown)
- Dvoluntary action cannot(4 more words not shown)
- Ethere is a(10 more words not shown)
Reading the argument
Why can't both things influence us?
The researcher contrasts chemical control with human choice. But choosing how to act doesn't obviously mean chemicals have no influence on the choice. A person might think through a decision while also feeling impulses with a chemical basis. That's a possibility the argument needs to address before dismissing pheromones as mere leftovers.
“Vestige” means a remnant. The researcher isn't denying that humans still produce these chemicals. The claim is that psychological factors have taken over their behavioral role. The support is that human actions are voluntary, while the animal behavior is involuntary.
What we’re looking for
For the required assumption, I'd look for the rule that makes those explanations mutually exclusive. The argument needs voluntary choice to rule out a chemical explanation. Otherwise, the evidence about free will can be true while chemicals still help explain how humans behave.
Working the answers
- A
This begins by ruling out a chemical explanation and then concludes that the explanation must be psychological. But the researcher starts with voluntary choice and uses it to rule out the chemical explanation. A doesn't justify that step.
Even if every nonchemical explanation were psychological, a voluntary choice might still have chemical influences. That's the possibility the argument needs to exclude, and A leaves it open.
- BCorrect
The researcher relies on the idea that voluntary action cannot have a chemical explanation. That is what allows the move from humans choosing their behavior to chemicals no longer playing the relevant role.
Suppose voluntary action could have a chemical explanation. Then calling human behavior voluntary wouldn't eliminate pheromones as part of its explanation. The researcher's evidence would no longer support dismissing them in the way the conclusion does. B supplies the exclusion the reasoning requires.
- C
The argument doesn't need every other animal to lack free will. It describes the relevant behavior in some animals and contrasts that behavior with human choice. Another kind of animal could have free will without changing the proposed reasoning about humans.
- D
An evolutionary explanation concerns how a capacity developed. It isn't the same as a chemical explanation of behavior. Human voluntary choice could have an evolutionary history while the researcher still argued that psychological factors now govern it. The required exclusion is the one in B.
- E
This asks why humans continue producing pheromones. The researcher instead offers a psychological explanation for human sexual behavior. Those are different things to explain. The chemicals' continued presence could be a remnant of evolution, just as the conclusion says, without itself having a psychological explanation.
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