Logical Reasoning

PT133 · S3 · Q18 The probability of avoiding

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The probability of avoiding heart disease is increased if one avoids fat in one's diet.

Conclusion

If you avoid dairy foods, avoid >> prob GH probability of maintaining dairy increased good health is increased.

Evidence

If you avoid dairy foods, avoid >> eat less you're less likely to eat fat dairy fat

If you avoid eating fat, avoid prob of probability of avoiding fat >> avoiding heart disease goes up HD goes up

Evaluation

The author is arguing this causal chain:

avoid >> eat less >> prob of >> prob GH dairy fat avoiding increased HD goes up

We go from talking about "being less likely to eat fat" to "avoiding fat in one's diet". There's a little different there, so an answer could call out that gap.

But more likely to be addressed in the answer is the last gap, where we go from saying "you've increased the probability of avoiding heart disease" to "you've increased the probability of maintaining good health".

Goal

Look for an answer that addresses the difference between avoiding heart disease and maintaining good health.

18.

The reasoning in the argument is most vulnerable to criticism on which one of the following grounds?

Correct
The argument ignores the possibility
Why this is right
Is there a practice that may have potentially negative consequences here? Sure, we could flip the chain we discussed and say that eating more dairy can lead to more fat which can lead to an increased risk of heart disease. Is the author ignoring the possibility that eliminating dairy might also have negative consequences? Sure, maybe by cutting out dairy you don't get enough calcium or protein and suffer osteoporosis or some other sort of problem. In a sneaky way, this answer addresses the separation of between "lessening your risk of heart disease" and "maintaining good health". It's saying, "before you cut out dairy, because of the negative risk associated, you should probably what good it's doing for you and what potential negative risks to your overall health are associated with having no dairy." If an answer has the syntax "fails to consider that EVEN IF ⎽⎽⎽⎽ , it may still be ⎽⎽⎽⎽⎽", then it will work as long as it's saying "fails to consider that EVEN IF [something from the evidence], it may still be that [something that would hurt the conclusion]".
Skill tested: Flaw · how this choice captures the argument's function is the move to repeat next time.
60% picked this
The argument fails to consider
No Impact
This feels pretty tempting, because we might think about objecting "Why do we have to get rid of dairy, which might do some good things for us? Maybe there's a different way to get less fat and thus less risk of heart disease?" The problem with that is that this author never said we need to get rid of dairy for the sake of reducing our heart disease risk or improving our chances of maintaining good healthy. He only said that if we got rid of dairy, we would see these salutary results. We can only arguing with him by saying "quitting dairy would not leave us better off". It's not an objection to anything he said to say, "Doing something else could be even better for our health".
9% picked this
The argument presumes, without providing
Out Of Scope: ought
There's nothing normative or prescriptive in any of this language, so we can't accuse the author of saying we should eliminate dairy. Her argument is only describing what would happen if we did eliminate dairy.
3% picked this
The argument fails to show
Not Accurate
Since the conclusion is about "if you quit dairy, ⎽⎽⎽⎽ would happen" and the evidence includes "if you quit dairy, ⎽⎽⎽⎽ would happen", it's self-evident that the evidence is relevant to the conclusion. Naturally, the evidence is not proof of the conclusion, but our complaint with this logic isn't that the premises are totally irrelevant.
18% picked this
The argument fails to consider
No Impact
The author is only talking about increasing / decreasing probabilities. She is never promising that something probable will occur, so we can't object to her by saying, "Sometimes things that are probable don't occur".
10% picked this

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