Logical Reasoning

PT149 · S3 · Q26 Decreased reliance on fossil fuels

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Decreased reliance on fossil fuels is required if global warming is to be halted.

Premise 1 (conditional)

Ending global warming To do X → Y requires ↓ fossil fuels requires

Premise 2 (conditional)

$ incentives for alt energy if Z → Y leads to ↓ fossil fuels then

Conclusion (conditional)

Ending global warming To do X → Z requires offering $ requires incentives for alt energy

Evaluate

Like so many proud Parallel Flaw before him, this guy is doing the Necessary vs. Sufficient flaw.

We know that ending global warming requires decreased reliance on fossil fuels.

One sufficient means of getting less reliance on fossil fuels is if there were economic incentives to develop alternatives. But the author's conclusion is acting like those economic incentives are required.

Goal

We need two conditional premises, both of which point to the same outcome. X → Y Z → Y

Then the conclusion should (erroneously) conclude that there's some conditional connection between the two trigger ideas. X → Z

Or, conversationally, we need to see the author act like something sufficient is instead something required.

26.

The flawed pattern of reasoning exhibited by the argument above most closely parallels that exhibited by which one of the following?

If we end poverty we
Bad Premise Match / Valid
These two premises chain together, so the argument is valid. End poverty → End hunger End unemployment → End poverty We want two conditionals that have the same outcome, so they don't chain together.
6% picked this
Daily exercise guarantees good health.
Bad Premise Match
These two premises chain together. good health → happy life daily exercise → good health We want two conditionals that have the same outcome, so they don't chain together. Original argument This argument X → Y X → Y Z → Y Y → Z so, X → Z so, Z → X
7% picked this
Going to college is required
Bad Premise Match / Valid
These two premises chain together. college → graduating getting professional job → college We want two conditionals that have the same outcome, so they don't chain together. Original argument This argument X → Y X → Y Z → Y Y → Z so, X → Z so, X → Z
10% picked this
Correct
Keeping good teachers is necessary
Why this is right
These two premises have the same outcome. improving education → keeping teachers improve teachers salaries → keeping teachers Then the answer concludes a conditional relationship between the triggers. improving education → improve teachers salaries To improve education we need to keep teachers in the profession. Improved salaries are one possible way to keep teachers in the profession, but the author is acting like improved salaries are necessary to keep teachers in the profession.
Skill tested: Parallel Flaw · how this choice captures the argument's function is the move to repeat next time.
65% picked this
Preventing abuse of prescription drugs
Bad Premise Match
These two premises chain together. expand education → cooperate ↑ prevent abuse → expand education We want two conditionals that have the same outcome, so they don't chain together. Original argument This argument X → Y X → Y Z → Y Y → Z so, X → Z so, Z → X This argument ends up being flawed because it reads the chain backwards. We knew X → Y → Z, and it concludes Z → X, but that's a different flaw from the original, in which the two conditional premises didn't chain together at all.
12% picked this

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