Logical Reasoning

PT18 · S4 · Q22 Doctors in Britain have long suspected

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Doctors in Britain have long suspected that patients who wear tinted eyeglasses are abnormally prone to depression and hypochondria.

Conclusion

When people wear tinted glasses, we can be sure that the person wearing them tends to be depressed or hypochondriacal.

Evidence

Doctors have long thought that patients who wear tinted glasses are abnormally prone to depression and hypochondria (and then psych tests given to hospital patients confirmed that correlation).

It's possible that if you were depressed, you would choose to wear tinted glasses to reduce irritating visual stimulation.

Evaluate

This seems to be a good ol' Curious Fact / Explanation setup.

Curious Fact Why is it that there's a correlation between depression/hypochondria and wearing tinted glasses?

Author's Explanation Being depressed causes someone to want to see less visual stimulation, so they choose to wear tinted glasses.

A correct answer will either deal with - an Alternate Explanation for that curious fact or - the plausibility of the Author's Explanation

We know whenever we see correlations to consider the alternate explanations of Reverse Causality and Third Factor.

Reverse Causality -- maybe the tinted glasses came first, and it made people feel depressed and sick (hypochondriacal)

Third Factor -- maybe some underlying cause leads to both depression and a desire for tinted glasses.

Goal

Since this is Necessary Assumption, the correct answer will either rule out an alternate explanation for the correlation, or it will establish something that's necessary for the author's story to make sense.

22.

The argument assumes which one of the following?

  1. Depression is not caused in

    Too Strong: never organically caused

    It wouldn't hurt the author to think that depression is caused by an organic condition, so there's no reason that he needs to assume this isn't the case.

    16% picked this

  2. Wearers do not think of

    Negation Does Nothing

    If people who wear tinted glasses do think of them as a means of distancing themselves from other people, does that provide an alternate explanation for the correlation between depression/hypochondria and tinted glasses? No. Would the negation hurt the plausibility that tinted glasses wearers always have depression or hypochondria? Nope. It would actually fit very nicely with the author's story that the wearer is depressed or is a hypochondriac -- both conditions are associated with people not wanting to be close to other people. Since the negation would either do nothing or strengthen, there's no reason to say the author needs to assume this idea.

    11% picked this

  3. Depression can have many causes,

    Irrelevant: many causes

    The author never talks about what causes depression, so whether there are many causes or one cause is not going to change anything the author said (unless we were told that one cause of depression was wearing tinted glasses!)

    7% picked this

  4. For hypochondriacs wearing tinted glasses,

    Negation Doesn't Weaken

    If this were true, it would somewhat fit plausibly with the author's story that people wearing tinted glasses are doing so because they are depressed or have hypochondria. But if we negate this it doesn't weaken at all. It's not an objection to this argument to say that hypochondriacs wearing tinted glasses are not trying to warn others that their health is delicate.

    5% picked this

  5. Correct

    The tinting does not dim

    Why this is right

    And here comes Reverse Causality, stepping up to the plate. If we negate this, we get the classic Reverse Causality objection to an author's "if X and Y are correlated, then X causes Y" logic. negation: the tinted glasses do cause the person wearing them to have a depressed mood. This offers an alternate explanation for the correlation between tinted glasses and depression. It's not that people are wearing tinted glasses because they're depressed. It's that people are depressed because they're wearing tinted glasses.

    Skill tested: Necessary Assumption · how this choice captures the argument's function is the move to repeat next time.

    61% picked this

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