Logical Reasoning

PT106 · S3 · Q22 Researcher: The role of chemicals

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Researcher: The role of chemicals called pheromones in determining the sexual behavior of some animals is well documented.

Main Conclusion (it is clear that / thus)

It's clear that psychological factors have taken over the role pheromones play (for other animals) in determining sexual behavior.

Intermediate Conclusion (So)

Pheromones are merely a vestige of our evolutionary past.

Evidence

For animals, sexual behaviors are involuntary, which shows they're being controlled by chemicals (pheromones).

For humans, who have free will, behavior is voluntary.

Evaluate

This is a bit of a mess. I'm not even 100% willing to stand behind the Main vs. Intermediate conclusion divide.

If we focus on the conclusion that , are we convinced?

It seems like premises are forcing us to believe that psychological factors from free will are kicking in, but I guess I'm wondering if it's clear whether they "take over".

Couldn't human sexual behavior be a product of both psychological factors and pheromones?

If we focus on the conclusion in the last sentence, we need to think about proving the idea that something is a "vestige of our evolutionary past".

We would create a linking assumption such as, .

The idea of "vestige" is sort of like obsolescence. Because we have free will, we don't need/use pheromones.

So, it seems like we could weaken the argument by showing that pheromones still have some current usefulness in human life. Maybe that's by explaining how they assist free will in picking good mates. Maybe pheromones do something for us that isn't related to sexual behavior.

Goal

Stay flexible. If we negate it, it should sound like an objection.

The author's main ideas here are that animals and humans are different when it comes to pheromones. Because we have free will, our sexual behavior is voluntary and thus controlled by psychological factors. And if we're not using pheromones for this / if they're not taking over, then they are just a vestige of our evolutionary past.

22.

The researcher's argument requires the assumption that

Whatever does not have a
Too Strong: whatever / purely
This argument was only about sexual behavior. It did seem like the author was saying that for humans, sexual behavior should be explained psychologically, not chemically. But he didn't necessarily assume that every single thing in the universe that doesn't have a chemical explanation must be purely psychological. We can ask ourselves if he ever made this move: from -- X doesn't have a chemical explanation, to -- X must have purely psychological explanation Not really. It was more like the author was thinking, "whatever has an explanation that is influenced by free will must have a purely psychological one".
6% picked this
Correct
Voluntary action cannot have a
Why this is right
Does the author ever make this move? voluntary action ? ~chemical explanation Yes, in the second to last sentence, he's building a contrast between animals and humans: Animals Humans sex behaviors are sex behaviors are voluntary involuntary, (by virtue of free will), thus clear sign thus clear sign of of chemical control psychological control This answer is resisting that move. The author is Assuming a Difference between involuntary and voluntary actions. If we negate this answer, it attacks that assumption. If voluntary actions can also have a chemical explanation, then maybe pheromones explain how we go about making free will decisions, in which they're still a meaningful part of the human species' life, in which case they're not just a vestige of the past. This answer is tough because it seems contradictory to say that a voluntary action could be controlled by chemicals. But they don't say "controlled", they say "explained", and I think that's intended to mean more like "Why did I choose to ask Jill on a date? Because she just smelled really good when I got near her. And now I'm President!" That's an example of how pheromones would explain why someone with free will made a certain choice.
Skill tested: Necessary Assumption · how this choice captures the argument's function is the move to repeat next time.
69% picked this
Free will can be found
Too Strong: only
The argument didn't make a categorical divide between humans and all other animals in terms of free will. The first sentence only talks about some animals having pheromones determine their sexual behavior. When we're told that humans have free will, we're not told it's a unique capacity we have. The author may well believe that dolphins have free will as well. That wouldn't hurt anything in the argument.
9% picked this
Voluntary action cannot have an
Too Strong
Did the author make a move like this? action is ? not explained voluntary by evolution No. The only time the author brought up evolution was to say that chemical pheromones were part of how we evolved but are no longer important to us (perhaps because we evolved free will).
8% picked this
There is a psychological explanation
Opposite, if anything
I don't really even know how to classify this answer because it seems to just be fabricating a brand new meaning by putting words from the paragraph in a new order. The author's explanation for the continuing presence of pheromones in humans is that it's a vestige of our evolutionary past (that's not a psychological explanation). As fetuses, we still have a stage where we have vestigial tail (some are even born with a small tail). That stage of development still exists as a relic of our evolutionary history. The author is suggesting something similar for pheromones.
8% picked this

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