Logical Reasoning

PT155 · S4 · Q2 Brian: I used to eat cheeseburgers

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Brian: I used to eat cheeseburgers from fast-food restaurants almost every day.

Conclusion (This proves that)

Eating bread and meat in the same meal is unhealthy.

Evidence

I used to eat fast food burgers almost every day, until I read that eating bread and meat in the same meal interferes with digestion.

So now I'm eating lean meats, fruits, and vegetables and I feel much better and my cholesterol level and blood pressure are lower.

Evaluate

The author is trying to solve the causal mystery of why he feels better on his new diet, so we can use an Explain Curious Fact mindset.

Curious Fact ... why do I feel better and have lower cholesterol and blood pressure since I switched from daily fast food burgers to a diet of lean meats, fruits, and vegetables?

Author's Explanation ... It's because I was eating bread and meat in the same meal, which supposedly interferes with digestion, (and thus made me feel worse and caused higher cholesterol and blood pressure)

When we see this template arise on Flaw, the correct answer is almost always complaining that the author has failed to consider some Alternate Explanation for the curious fact. What could be a different explanation for why he's doing better on the new diet?

We could say,

We could also say,

Goal

Look for an answer complaining that this author has failed to rule out some alternate explanation for his improved condition (or one complaining that this hypothesis isn't a plausible one, since improved digestion might have anything to do with lower cholesterol and blood pressure).

2.

The reasoning in Brian's argument is flawed in that the argument

  1. treats a statement as established

    Not Inappropriate Appeal to Expert

    This is referencing one of the 10 famous flaws, Inappropriate Appeal to a Dubious Expert. There is no self-appointed expert mentioned. The author definitely acted on an idea she read somewhere, but she never talks about someone who considers themselves an expert and whose opinion she treats as fact.

    2% picked this

  2. draws a conclusion that merely

    Not Circular

    This is referencing one of the 10 famous flaws, Circular reasoning, in which a premise restates the conclusion or presumes its truth. These answers are almost always wrong. The conclusion is that "eating bread and meat in the same meal is unhealthy", and there is definitely not a premise that restates that claim ("interferes with digestion" ≠ "is unhealthy").

    1% picked this

  3. treats a condition that must

    Not Necessary vs. Sufficient

    This is referencing the most common of the 10 famous flaws, Necessary vs. Sufficient, in which an author presents a conditional logic premise and then applies it in some illegal reversed or negated fashion. There was no conditional logic premise, so she can't be guilty of an illegal reversal or negation.

    2% picked this

  4. Correct

    concludes that one part of

    Why this is right

    The author concludes that "discontinuing having bread and meat in the same meal" is why she feels better and has lower cholesterol and BP. Meanwhile, it's possible that splitting up bread and meat was not the change that is really responsible for the improved condition. Maybe it was the change of "not eating fast food almost every day". Maybe it was the change of "eating fruits and veggies". This argument is dealing with another of the 10 famous flaws, Causal Overconfidence, in which the author overconfidently concludes one causal explanation for a curious fact while failing to consider other possible explanations.

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

    93% picked this

  5. concludes that making a dietary

    Bad Evidence Match

    The author does conclude that making the dietary change of splitting up bread and meat improved their particular health. But she does not conclude this on the basis of evidence that said, "most people who stop combining bread and meat end up with improved health".

    1% picked this

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