Logical Reasoning

PT140 · S1 · Q3 Peter: Recent evidence suggests

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Peter: Recent evidence suggests that moderate alcohol consumption has certain beneficial effects on health.

Conclusion

Alcohol consumption is, on balance, beneficial.

Evidence

According to recent evidence, moderate alcohol consumption has certain beneficial effects on health (such as killing off some bacteria that can cause illness).

Evaluate

Given That ... moderate alcohol consumption seems to have some beneficial effects How Could We Argue That ... alcohol consumption is not beneficial overall?

We'd probably have to say that the author is failing to talk about the downsides of alcohol consumption (empty sugars? raises blood pressure? hurts liver?), and that the downsides might outweigh the "certain beneficial effects" such as killing off some harmful bacteria that would be living in your mouth / throat.

Goal

Look for an answer that says the author is only presenting part of the story. If we're trying to conclude that something is "on balance / overall" beneficial, then we should have laid out all the pros, all the cons, and established that the pros outweigh the cons.

Which one of the following most accurately expresses a flaw in the reasoning in Peter's argument?

It takes for granted that
Out of Scope: because they believe
The author hasn't mentioned anything about what people do / don't believe about alcohol or speculated in any way about why people drink, so the author hasn't committed to any assumptions about why people choose to drink alcohol. If you negated this idea and said "people don't drink because they believe alcohol is beneficial", the author's argument wouldn't be weakened. She'd just say, "Cool, I never said that's WHY they drink; it just so happens to be an effect of them drinking."
2% picked this
It draws a comparison based
Out of Scope: popular belief
Does the author draw a comparison? Nope. Is there reference to a popular belief? Nope. Is there a scientific opinion? Yeah, we could probably consider "recent evidence suggests" a scientific opinion. So all three parts of this answer don't match. Appealing to people's belief rather than actual scientific data is a famous flaw known as Inappropriate Appeal (to Opinion).
1% picked this
It fails to consider methods
Not an Objection
Does it hurt the author's argument if we say, "Yo, my dude -- there are other ways to make your body an inhospitable environment than consuming alcohol", the author would just say "Sure, I know. I never said alcohol was the only substance that had these beneficial effects, just that it is a substance with these beneficial effects."
13% picked this
Correct
It draws a conclusion about
Why this is right
Does the author draw a conclusion about alcohol consumption in general? Sure, the conclusion just says "alcohol consumption is beneficial". Is the author's premise about moderate alcohol consumption? Yes -- she says that moderate alcohol consumption has certain beneficial effects on health. But maybe light alcohol consumption or heavy alcohol consumption doesn't have those benefits. (perhaps light alcohol consumption is not enough to render your insides inhospitable to bacteria, whereas heavy alcohol consumption starts to be very damaging to your heart/liver) By shifting from evidence about a subtype of alcohol consumption to a conclusion about all types of alcohol consumption, the author is making a Sampling assumption that what is true of moderate consumption is also true of light / heavy consumption. We could object to the author by saying, "Even though moderate alcohol consumption can have beneficial effects, light alcohol consumption is totally neutral and heavy alcohol consumption is very damaging. Thus, we can't really just generalize that alcohol consumption is, on balance, beneficial."
Skill tested: Flaw · how this choice captures the argument's function is the move to repeat next time.
74% picked this
It fails to consider that
Not an Objection
The author didn't promise that alcohol killed 100% of bacteria, so pointing out that it has no effect on many bacteria isn't an objection. It might even be that alcohol doesn't kill off the good bacteria that's part of a healthy gut. That would actually help the author's case. Something doesn't need to be a perfect/total solution to be a beneficial action.
10% picked this

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