Logical Reasoning

PT124 · S2 · Q13 Researcher: People with certain personality

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Researcher: People with certain personality disorders have more theta brain waves than those without such disorders.

Conclusion

Watching too much TV increases your risk of developing a personality disorder.

Evidence

Watching TV increases theta waves + People with certain personality disorders have more theta brain waves than average.

Evaluation

This author is committing the famous Correlation vs. Causality flaw, which is a specific flavor of Causal flaws. Some personality disorders are correlated with higher than average theta waves.

Our author is assuming that those higher theta waves caused the personality disorder. That's why he's worried that watching TV will lead to a personality disorder. He's picturing this chain of causality: watch lots of tv → more theta → personality disorder

Goal

Look for an answer calling out his illegal correlation to causation move, or an answer that suggests a different way to interpret that same correlation (maybe having the personality disorder causes the higher theta waves, or maybe some third factor separately causes the personality disorder and the higher theta waves)

13.

A questionable aspect of the reasoning above is that it

  1. uses the phrase “personality disorders”

    Not Equivocating

    Both usages of "personality disorder" mean the same thing, a clinically diagnosable psychological condition. This answer choice refers to the famous flaw Equivocation, which will almost always be an incorrect answer.

    0% picked this

  2. fails to define the phrase

    Not a Flaw

    We're never saying that "the problem with this guy's reasoning is that he didn't precisely define a term or provide an exact measurement or specifically name his sources". It wouldn't matter if this argument replaced "theta brain waves" with "any three words". The reasoning problem would be the same.

    0% picked this

  3. Correct

    takes correlation to imply a

    Why this is right

    The language of "People who are X have more Y than people who aren't X" is a correlation. It strengthens the idea that there's some connection between X and Y, but we can't confidently assume that X causes Y.

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

    90% picked this

  4. draws a conclusion from an

    Bad Evidence Match

    We haven't been given any reason to think that the data set is unrepresentative. This answer choice refers to the famous flaw Sampling, but when they are testing unrepresentative samples there are some crumbs in the evidence to suggest that we're dealing with a biased or self-selecting sample.

    6% picked this

  5. infers that watching TV is

    Bad Conclusion Match

    The author is envisioning a causal chain that looks like this: watch TV ? more theta ? personality disorder The author is inferring that personality disorder is a consequence of watching too much TV.

    3% picked this

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