#22 - Researcher: The role of chemicals called pheromones in

[8scn]

What was the thinking process used to get B as the correct answer? I was deciding between A, B, and D but couldn't figure out which answer was best.

[Administrator]

Hi, can you clarify your thinking on this question? The more information you provide about your thought process, the more easily we can assist you.

Thanks!

[8scn]

Hi, my reasoning was: the stimulus says that psyc factors have taken over the role of determining sexual behaviour in humans, and this is because they have free will. This is contrasted with animals who display involuntary sexual behaviours because their behaviour is chemically controlled. Then the conclusion states that pheromones are a vestige humans’ evolutionary past.

So my prephrase was that involuntary behaviours that are chemically controlled are a vestige of our evolutionary past, whereas voluntary behaviours that are psychologically controlled are not.

For A: I thought this was supported by the fact that since human behaviours are primarily psychologically controlled and not chemically controlled.

For B: I can see how it could be correct, but why is it the best answer?

For D: I thought that because human behaviours are voluntary, but they have a psychological explanation, not chemical, so they don’t have an evolutionary explanation.

[Nikki Siclunov]

The stimulus is structured as follows:

Premise: Involuntary behavior in animals indicates chemical control.

Premise: Sexual behavior in humans is voluntary.

Sub-Conclusion: Sexual behavior in humans is a function of psychological factors.

Conclusion: Pheromones are a vestige of our past (i.e. chemical factors no longer play a role in our sexual behavior today)

To identify the Assumption, we need to figure out what the argument depends on. Just because human sexual behavior is voluntary does not necessarily mean it is entirely explainable by psychological factors: there is a gap in the reasoning that we need to assume NOT to exist. Let's look for a Defender Assumption stating that voluntary behavior is only explainable by psychological factors.

(A) is attractive, but it goes too far. The assumption isn't that whatever does not have a chemical explanation must have a purely psychological one; we are only concerned with voluntary behavior. Answer choice (A) may serve to strengthen the argument - or even justify its conclusion - but it is not a necessary assumption upon which the argument depends.

(B) is correct. To prove it, let's apply the Assumption Negation technique: voluntary action can have a chemical explanation. If so, then it is no longer certain that sexual behavior in humans (which is a voluntary action) is a function only of psychological factors. Because the logical opposite of (B) weakens the conclusion, it is the correct answer to an Assumption question.

(D) is incorrect, since the logical opposite of (D) does not weaken the argument. Even if voluntary actions can have evolutionary explanation, it is still possible that pheromones are no longer relevant in how such actions manifest themselves. The author never argued that human sexual behavior is not the result of evolution; the argument is merely that chemical factors, which are vestiges of our evolutionary past, no longer affect such behavior.

[temiolof]

Hi,

I wavered between A and B and ultimately chose B, but when I negate answer choice A, it seems to weaken the argument: If we say "Whatever does not have a chemical explanation cannot have a purely psychological one" (I'm not actually sure if this is the correct negation. Should I also remove "not"?), it seems this statement would undermine the argument, which says because humans have free will/produce voluntary behavior, their sexual behavior cannot be chemically controlled and, instead, must be psychologically controlled. Or would the answer still be wrong based on the word "purely"? I'm not sure that stating that "psychological factors take over" implies these factors are the only ones affecting sexual behavior.

Also, If I understand correctly from the response above, answer A is incorrect because it casts too wide a net (fills logical gap over 100%) in stating "whatever" as opposed to the specific subject presented in the stimulus. If we substituted "whatever does" for "voluntary behaviors that do" in answer choice A, would it be an assumption required by the argument? I assume it wouldn't because this is a required assumption question, an answer choice that fills the gap 100% or more is sufficient, but not required, and therefore wrong. A required assumption answer, however, can be a subset of the gap.

Essentially is there another reason why A is wrong?

Thank you.

[Francis O'Rourke]

Hi Temi,

Nikki’s explanation above for Choice (A) is the most concise way I can imagine explaining it; once you recognize that an answer choice goes too far, it cannot be required. This will be most helpful for you to eliminate answers quickly on the test.

Now on to the longer explanation of choice (A). The negation does not significantly rebut the argument. You’re very close to correctly negating choice (A), but instead the negation should be:
whatever does not have a chemical explanation does not necessarily have a purely psychological one
To negate a conditional statement, negate the necessary condition by indicating that it is not necessary. So the negation of choice (A) states that if you do not have a chemical explanation, you may or may not have a psychological explanation. This is not a very strong statement, and will not weaken the conclusion at all.

[ksikanon]

Could another necessary assumption for this argument be that pheromones are not necessary for voluntary action? I understand why (D) is correct, but want to see if I can find some other necessary assumptions.

[Jennifer Janowsky]

Hey, Ksikanon! That could definitely be another assumption, and negating it shows that. Sounds like a good way to practice!

[bonnie_a]

I got this question right but I want to further ask about the answer choice (E). Is (E) wrong because it talks about the "continuing" presence of pheromones? Though humans produce them, the author's point is they no longer play the role of determining/affecting the sexual behavior in humans. Since the focus is not on its continued presence, (E) doesn't have to be true here...?

[atierney]

Hi Bonnie,

E is wrong because the argument doesn't have to explain why there are still chemicals in human beings, or even these particular chemicals, the pheromones. Just like you said, the focus isn't on the chemicals' continued presence; the key is whether these chemicals control or even play a role in the human experience of free will (voluntary action), as explained by answer choice B. I would mainly classify answer choice E as an irrelevant answer because it doesn't do anything to explain or add to the main idea that rather than by virtue of primal chemical dependence, human beings are able to exhibit voluntary choice in mating (or so the Germans would have us believe!)

Let me know if this is clear! Otherwise, basically E is not a relevant answer/assumption for the argument.