Logical Reasoning

PT147 · S1 · Q6 Some have argued that body size

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Some have argued that body size influences mating decisions throughout all societies.

Conclusion

Body size influences mating decisions throughout all societies.

Evidence (argument rests on)

Just look at the self-reports of college-age students, and look at personal advertisements in newspapers for dating partners.

Evaluate

This argument is presented in a really weird style. We're being told what some people have concluded, and we're being told what sort of evidence they consulted, but there isn't actually any evidentiary claim presented. Like, what were the self-reports of college age students? When they analyzed personal ads for romantic partners, what did they find?

We don't get any supporting premises; we only hear where the author got his premise, and so we're apparently supposed to find Flaw with that itself.

It's sort of like if we heard,

We're supposed to react to the Evidence and say that the flaw is that . Why would you ask old people what kids want for Christmas? They're going to tell you what a kid in the 1950's wanted for Christmas, not what a modern kid wants.

So similarly, if you're trying to figure out whether body size influences mating decisions throughout all societies, then why should we criticize you for asking college students what influences their mating decisions, or for analyzing dating ads in the paper to see what's motivating their dating decisions?

Well, it's an incredibly shallow source of evidence, double entendré intended.

It's shallow as in way too small a sample. It's bad to extrapolate from what is true among college students and personal ads to what is true "throughout all societies".

It's also shallow as in not representative of all mating behavior. College students and people placing hook-up ads in the paper might be more focused on looks, whereas if you looked in more "wholesome" places you'd find people whose partner's body size did not play a meaningful role in their mating decision.

Goal

Look for an answer reacting to how ludicrously strong the conclusion is (X influences Y throughout all societies) based on the fact that the evidence considered is an incredibly narrow swath of the human condition (some college students' self-reporting and some personal ads in newspapers).

The reasoning in the argument described above is most vulnerable to criticism on the grounds that the argument

concludes that one kind of
Not Causal
This answer describes a variation of the famous Causal flaw, in which an author overconfidently concludes one causal explanation for something, without considering other possible explanations. Could we fairly say that the author concludes that "one kind of event causes another kind of event"? Not really. The conclusion is causal ('body size influences mating decisions'), but we can't really call 'body size' an event. And we didn't find ourselves yelling at this author, "Hey, man, maybe both body size and mating decisions are being caused by some 3rd factor."
0% picked this
Correct
bases a conclusion on a
Why this is right
This answer describes a variation of the famous Sampling flaw, in which an author's conclusion is a generalization / extrapolation, and the evidence is a sample that we criticize for being too small, an unrepresentative slice of the population, a self-selecting sample, or at high risk of having dishonest responses. The sample of "college students and personal ads" is likely to be unrepresentative of "mating decisions throughout all societies". Asking the co-eds at Arizona State or the users of Tinder how they make their mating decisions and expecting that their answers will be the same as if we asked a remote hunter-gather society in Ethiopia seems like a stretch. So the author should not be generalizing about all societies based on this incredibly narrow subset of data points.
Skill tested: Flaw · how this choice captures the argument's function is the move to repeat next time.
87% picked this
concludes that an effect has
Bad Conclusion Match
Could we fairly say that the author concludes that "an effect has only one cause"? No. The conclusion says 'body size influences mating decisions', which doesn't mean it's the only cause of mating decisions.
0% picked this
uses a claim that applies
Bad Conclusion Match
Does the author draw a conclusion about individual persons? No. The conclusion says 'body size influences mating decisions throughout all societies'.
1% picked this
draws a universal conclusion on
Too Strong: very small
It's pretty freaky that they would put another answer choice referencing the Sampling flaw. It does seem like the evidence is too small, given that the conclusion is about all the societies of the world. But can we say it's "a very small number of individual cases"? Not necessarily. We don't know how many university-age students were polled. We don't know how many personal ads were analyzed. And we're only told "their argument rests largely on" these things, so we also don't know what the rest of the evidence consisted of. If 1,000 students were questioned and 1,000 personal ads were analyzed, we would not call that a very small individual number of cases. But we could still say that it's a very unrepresentative slice of the mating-behavior pie. No matter how accurate a picture we have about the mating decisions of college students and people who place personal ads, we still won't feel comfortable assuming that their mating decisions are akin to those of all other people.
12% picked this

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