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#24 - In an effort to reduce underage drinking, the

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Complete Question Explanation

Flaw in the Reasoning—CE. The correct answer choice is (C)

This author discusses a recent Department of Health effort to reduce underage drinking by encouraging young people to take a pledge not to drink before reaching the legal age. Based on the fact that a survey showed that “many” who do not drink have taken the pledge, while the vast majority of those who drink have never taken such a pledge, the author concludes that the effort has been successful:

    Premise: ..... Many who do not drink have taken the non-drinking pledge.

    Premise: ..... Almost all drinkers surveyed have not taken the pledge.

    Conclusion: ..... Therefore the Department of Health has been successful in discouraging underage drinking.
The author’s argument is problematic. First, “many” is a very vague term, and second, the author has taken an apparent correlation and jumped to a causal conclusion. Just because there is some overlap between the people who don’t drink and those who have taken the pledge, that does not mean that the pledge was the cause of the decision not to drink (another distinct possibility: those who chose not to drink in the first place were much more likely to agree to such a pledge).

The question is followed by a Flaw in the Reasoning question, so the correct answer choice will be the one that describes one of the issues mentioned above (note also that in the case of a causal flaw, the correct answer choice will often have the words “cause,” “effect,” or some synonym).

Answer choice (A): The author does not use a judgement about the morality of underage drinking as a basis for the effectiveness of the pledge, so this choice should be ruled out of contention.

Answer choice (B): Had the author argued that the pledge was the best method of reducing underage drinking, there would have been a need to consider the possibility of more effective methods. In this example, however, the author merely argues that the effort seems to have been successful, so this is not the flaw in the author’s argument.

Answer choice (C): This is the correct answer choice. As discussed, the author takes an association between the pledge and non-drinking, and concludes the pledge must have been the cause.

Answer choice (D): This answer, which describes a Mistaken Reversal, does not describe the causal flaw reflected in the author’s argument.

Answer choice (E): The author does not confuse the claims discussed; rather, the author invalidly bases a causal conclusion on a mere correlation, so this choice does not accurately describe the flaw reflected in the stimulus.
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I got the answer C correct with the logic that the argument basically takes a correlation to mean causation
(~drink) & (Took the pledge) :arrow: (taking pledge) caused (~drink)

But I was confused about E.

E seems like it says something similar about causal or is it comparing two correlations?
E. confuses claim that (many adolescents who do not drink, report taking pledge) with claim that many (who report taking pledge, do not drink)

This is how I understood it:
(adolescents who don't drink, report taking pledge) - Adolescents whom already do not drink, then decide to take the pledge (the pledge didn't cause them to stop drinking since they already do not drink) CORRELATION
with the fact that (report having taken the pledge, do not drink) taking pledge CAUSES? them not to drink - or is this also another correlation.

So to me, I thought E was also identifying the correlation to causation flaw. Unless E is actually a correlation to correlation.

Thank you!
Jonathan Evans
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Hi, Jennuine,

First, good job getting it right. It is the case that the argument makes an unsupported causal inference.

With respect Answer Choice E, first you have to consider whether what the answer choice describes matches the flaw you have identified in the stimulus. In this case, the conversion of the subject and the predicate of the statement "many adolescents who do not drink report having taken the pledge" into "many who report having taken the pledge do not drink" describes neither a causal issue in the abstract nor the causal issue here in the particular.

Notice that there is no particular causal inference implied in these statements. Rather, these are categorical statements that flip whether the pledge takers don't drink with the non-drinkers taking the pledge. Is one a subset of the other or it is the other way around?

Notice here we're no longer talking about anything causal. Instead this is more of an issue of the distribution of one group onto another, whether some non-drinkers are a subset of pledge-takers or whether some pledge-takers are a subset of non-drinkers.

Symbolized, our premises are:

non-drinkers :some: pledge-takers
drinkers :most: non pledge-takers

As I hope is evident, Answer Choice E does not treat a causal issue. Excellent question, and I encourage you to continue to consider the kinds of flaws described in incorrect answer choices.
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This question made me think what the difference between correlation/causation confusion and causation/effect confusion is...
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I need some help making sense of what answer choice (E) is saying. Is there actually any difference between "many adolescents who do not drink report having taken the pledge" and "many who report having taken the pledge do not drink"? That is, is confusing the two claims actually a problem? Thank you very much!
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Hi nutcracker,

There isn't any logical difference between the two claims. Both statements essentially say that there is a correlation between (1) taking the pledge and (2) not drinking. The order in which this relationship is stated is irrelevant, since causal reasoning isn't used to describe the relationship between the two variables.

So you are correct that there is no problem with answer choice (E). It doesn't attack the argument. :)

Best of luck studying!

Athena Dalton