Logical Reasoning

PT141 · S4 · Q17 A positive correlation has been found

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A positive correlation has been found between the amount of soot in the atmosphere of cities and the frequency of a certain ailment among those cities' populations.

Conclusion (probably)

The soot itself probably doesn't cause this ailment.

Evidence (since)

Even though there's a positive correlation between amount of soot and frequency of the ailment, in cities where there are large amounts of soot, there are also usually high concentrations of many other air pollutants.

Evaluate

This argument is an Anti-Causal spin on the normal Explain the Curious Fact template.

Curious Fact ... why is there a correlation between atmospheric soot and ailment X?

Potential Explanation ... the soot causes ailment X.

Author's Anti-Causal Alternate Explanation ... No, the soot probably isn't causing ailment X. The ailment is probably being caused by other air pollutants, because the cities that have lots of atmospheric soot also have these other air pollutants.

Goal

If we're trying to weaken this argument, we'd like to either find an answre that helps us argue:

1. It is the soot that's causing the ailment 2. It's not these other pollutants that are causing the ailment (or both)

17.

Which one of the following statements, if true, most weakens the argument?

  1. In cities where there are

    Strengthens

    This answer suggests that soot is not the cause of Ailment X, so it strengthens this author's conclusion. If the ailment is still just as prevalent even in cities where there's not much soot in the air, then soot doesn't seem to be the cause.

    9% picked this

  2. If the ailment rarely occurs

    Untriggered Conditional

    The outcome of this conditional would be the perfect counterpunch to this author's conclusion, but we only get that outcome if we establish that the trigger is true. Do we know that the ailment rarely occurs except in cities in which there's lots of soot in the air? No, we've never been told that. Thus, this hypothetical idea has no impact.

    22% picked this

  3. Correct

    In each of the cities

    Why this is right

    This both strongly suggests that soot is the causal difference-maker and that the other pollutants are not. There are cities where there is high soot, but not the "other pollutants" that the author is thinking cause ailment X, and yet the incidence of ailment X is just as high as anywhere else. So that suggests that soot is what's causing the incidence of ailment X. If you believe that soot causes X, then we would say this data point strengthens by providing a "Yes Cause, Yes Effect" example. If you believe (as the author does) that these other pollutants cause X, then we would say this data point weakens by providing a "Effect without Cause" data point, since the effect is present (high incidence of X) even though the cause is absent (the other pollutants aren't there).

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

    60% picked this

  4. If high concentrations of many

    Strengthens, if anything

    This is also a conditional, so it doesn't have any value unless we can establish the trigger. If we do trigger the conditional, the outcome would actually help the author to argue that it's these other air pollutants that are causing the incidence of ailment X. The argument mostly establishes the trigger. Higher rates of ailment X are correlated with high levels of soot, and high levels of soot are correlated with high levels of these other pollutants. If A is correlated with B, and B is correlated with C, that doesn't necessarily mean that A is correlated with C, but it suggests it probably is. Luckily we don't need to dig deep on whether the trigger is established because the outcome wouldn't be helpful in terms of weakening the argument.

    5% picked this

  5. In cities in which there

    Somewhat Strengthens & Weakens

    This is an interesting answer, because it suggests that ailment X may actually be caused by some other form of pollution (not airborne). That somewhat goes against the idea the author is suggesting, which is that "other air pollutants" are causing ailment X, but it strengthens the author's conclusion that "the soot itself is probably not causing ailment X". If an answer is a mixed bag, it will almost always lose out to an answer that purely strengthens or weakens. The fact that this answer is saying "other forms of pollution very likely contribute causally to the ailment" also means that it's not actively denying the author's idea that air pollutants cause X. It can just be adding to that idea, saying "Yes and these other forms of pollution also contribute to X".

    4% picked this

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