Logical Reasoning

PT132 · S4 · Q13 Many symptoms of mental illnesses

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Many symptoms of mental illnesses are affected by organic factors such as a deficiency in a compound in the brain.

Conclusion

Organic factors that affect symptoms of mental illness are not evenly distributed around the globe.

Evidence

Many symptoms of mental illnesses are affected by organic factors, but there's tons of variation among different countries in the incidence of these symptoms.

Evaluation

Given that there's lots of variation around the globe when it comes to these symptoms, How could we still argue that the organic factors underlying these symptoms are evenly distributed around the globe?

That's a tough riddle to crack. If we want to argue that these organic factors are evenly distributed, then how would we explain why the symptoms vary so much around the world?

Maybe there's some combo of organic factors and other factors that combine, and it's the other causal factors that are unevely distributed?

Since the language here is that symptoms are affected by organic factors, it's possible that there is more than one thing affecting the symptoms.

Goal

Look for a way to explain why symptoms vary across the globe, even if organic factors are evenly distributed.

13.

The reasoning above is most vulnerable to criticism on the grounds that it

  1. does not say how many

    Not a Flaw

    We never need to be that precise with definitions or measurements to judge someone's reasoning. Does it make any difference to this argument whether there are 5 or 15 or 30 illnesses?

    2% picked this

  2. neglects the possibility that nutritional

    Opposite

    This seems to reinforce the idea that organic factors (such as organic compound deficiencies) are spread unevenly around the globe.

    17% picked this

  3. Correct

    fails to consider the possibility

    Why this is right

    This allows us to say that organic factors are evenly distributed, but there's a different causal factor that's unevenly distributed, hence the global variation in symptoms of mental illness.

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

    71% picked this

  4. presumes, without providing justification, that

    Too Strong: any

    The author doesn't have to make the very extreme assumption that every single change in brain chemistry noticeably changes your mental condition.

    5% picked this

  5. presumes, without providing justification, that

    Too Strong: any

    The author doesn't have to believe that mental phenomena are 100% caused by physical factors, just because she believes that many mental illness symptoms are affected by physical factors.

    5% picked this

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