Logical Reasoning

PT104 · S4 · Q24 Scientists, puzzled about the development

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Scientists, puzzled about the development of penicillin-resistant bacteria in patients who had not been taking penicillin, believe they have found an explanation.

Conclusion

The reason some patients who have not been taking penicillin develop penicillin-resistant bacteria is that they have mercury fillings.

Evidence

The genes that give bacteria mercury-resistance are in the same chromosomal spot as the genes that give bacteria resistance to penicillin (so there are probably bacteria that have resistance to both).

The mercury fillings in these patients' teeth are killing off all the bacteria, except the ones that have mercury resistance. But those are also the bacteria that have penicillin-resistance. That's why bacteria of the penicillin-resistant variety are emerging in the mouths of these people.

Evaluate

The question stem is asking us about the role of an unstated assumption, which is insanely weird. As far as I know, this is the only Role question that's ever asked about the role of an unstated claim.

Was the argument assuming that people who do take penicillin do develop penicillin-resistant bacteria?

Sure?

This is all so weird. Our outside knowledge is hopefully familiar with the concept of "super bacteria", the ones that have resistance to antibiotics, so the medical community is terrified of them. Doctors are scared to prescribe too many antibiotics, because when you give a patient an antibiotic, it kills off an entire class of bacteria. However, if some bacteria have a cool mutation that allows them to evade this antibacterial massacre, then they are the "last men on Earth", so they re-populate the world in their image.

Thus, the more we use antibacterial stuff, the more we're killing off the type of bacteria that our chemicals work on, and by killing off all that bacteria, we're enabling the scary kind of bacteria that our chemicals don't work on to proliferate more and more and potentially turn into the more dominant strain.

So we know / assume that people who take penicillin (an antibiotic), will kill off all the bacteria that's vulnerable to penicillin, leaving only the bacteria that are resistant to penicillin to survive and "re-populate the environment".

In the first sentence, what we didn't understand was why penicillin resistance would emerge in someone who wasn't taking penicillin, someone who wasn't taking a substance that would kill off all bacteria but the penicillin-resistant kind.

Goal

I have no idea what we should be looking for, because it's not playing any normal role like Main Conclusion, Support, Opposing, Neutral.

Of those, I would pick Neutral, because the thing they're asking us about is not even really relevant to the paragraph we read, which was about people who weren't taking penicillin.

Let's look for something like,

24.

Which one of the following most accurately characterizes the role played in the passage by the unstated assumption that some patients who take penicillin develop bacteria with an immunity to penicillin?

It is a hypothesis that
Too Strong: conclusively proven Unsupported Relationship
This paragraph had, like, nothing to do with the unstated assumption they're asking us about, since our paragraph is about people who didn't take penicillin, and the claim they're asking us is about people who do take it. This paragraph was definitely not conclusively proving anything about some people who do take penicillin.
11% picked this
It is a generalization that,
Unsupported Relationship
This is saying that "if people who do take penicillin develop resistant-bacteria, that rules out the possibility that people who don't take penicillin develop resistant-bacteria." Huh? That's certainly not true. That's like saying, "if people who had previously read Harry Potter liked the movie, that rules out the possibility that people who had not previously read Harry Potter liked the movie." That's crazy talk. Both groups of viewers might like the movie. Both types of people might develop penicillin-resistant bacteria. In fact, it's not like we have to even talk about it as a possibility. The first sentence straight up tells us that such people exist. No unstated assumption, if true, can rule out the possibility of something we've already been told exists.
5% picked this
Correct
It is a point that,
Why this is right
This is still somewhat weird, but we can make a stronger case against all the other answer choices. Essentially, this answer is saying ... Our normal background assumption, that people who do take P can develop P-resistant bacteria + The first sentence's puzzling fact, that people who don't take P are also developing P-resistant bacteria ... frames the question that the rest of the paragraph is trying answer. The first sentence, along with this unstated assumption, help to create the paradoxical mystery that scientists are puzzled by. Honestly, it feels weird to give this claim any "credit" for doing anything, because the paragraph already made sense without it. If we have a common sense understanding of where penicillin-resistant bacteria come from, then it's self-sufficiently puzzling to read the first sentence and wonder how these people who aren't taking an anti-bacterial substance are still developing resistant bacteria.
Skill tested: Role · how this choice captures the argument's function is the move to repeat next time.
67% picked this
It is the tentative conclusion
Wrong Role
As soon as we see the word conclusion we should be long gone. We never even met this guy before. Now you're telling me I'm married to him? What I mean by that is we shouldn't be tempted to give this random passerby such an important role in this paragraph. We weren't talking about him. We weren't referring to him as a previous research conclusion. We weren't trying to falsify him. This assumption has almost nothing to do with the conversation of the paragraph, because the paragraph is trying to solve a causal mystery about people who don't take penicillin.
4% picked this
It is a generalization assumed
Too Strong
Too Strong: conclusively prove Too Strong: must involve reference Again, I would be turned off by using such strong and important language for a random claim we just met when we reached the question stem. There was nothing integral about this claim because it wasn't even on our radar as we read the passage. Thus, it would seem way off to refer to it as something that conclusively proves their solution to the causal mystery must involve the genetics of penicillin-resistant bacteria.
13% picked this

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