Logical Reasoning

PT141 · S2 · Q5 Science writer: Lemaitre argued

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Science writer: Lemaitre argued that the universe began with the explosion of a "primeval in atom," a singular point of infinite gravity in space and time.

Conclusion

Lemaitre's theory (that the universe began with the explosion of a singular point of infinite gravity in space and time) must be considered inadequate.

Evidence (because)

Even though his theory predicts galaxies accelerating away from one another, which matches our observations, there is another theory (oscillating universe) that makes exactly this same prediction.

Evaluate

When your theory predicts X, and we observe X, that counts as evidence for your theory (definitely not proof of your theory).

If someone else's theory also predicts X, and we observe X, then where does that leave your theory?

In the same exact spot! Both your theory and this other person's theory both have some support. At this point, we wouldn't have any reason for believing more in yours or in theirs.

Yet our author here thinks that if someone else's theory also predicts X, then that shows your theory must be inadequate. This doesn't make any sense. Their theory making the same correct prediction as our theory shows us that the two theories are currently tied, in terms of how accurate they seem.

Goal

Look for an answer complaining that

5.

Which one of the following most accurately describes a flaw in the science writer's reasoning?

  1. The conclusion is derived partly

    Out of Scope

    Out of Scope: appeal to an expert One of the ten famous flaws is Inappropriate Appeal (to Emotion or a to dubious expert). This is not committing that flaw since none of the evidence provides an assertion attributed to a purported expert. The only attributed assertion is Lemaitre's theory, but that's not part of the author's evidence; that's what the author is trying to refute.

    2% picked this

  2. The conclusion is based on

    Not Equivocation

    This answer refers to another one of the ten famous flaws, Equivocation, which is almost never the correct answer. There was no term being used two different times in two different ways.

    1% picked this

  3. The science writer takes for

    Not Causal

    This is presenting language that sounds like another of the ten famous flaws, Causal Overconfidence, in which an author presents a funky fact (like a correlation) and then overconfidently concludes one possible explanation for the fact, while failing to consider other possible explanations. This argument has nothing to do with presenting a correlation and then concluding that one thing caused the other. This argument is saying, "Since Theory X makes the same observed prediction as Theory Y, Theory Y must be inadequate".

    5% picked this

  4. Correct

    The science writer fails to

    Why this is right

    This is saying the author fails to understand that just because the oscillating universe theory (O.U.T.) correctly predicts that galaxies accelerate away from each other, that doesn't do anything to make Lemaitre's theory look bad. His theory also makes that prediction.

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

    86% picked this

  5. The science writer presumes, without

    Too Strong: only

    The argument only presented two explanations for why galaxies are accelerating away from one another, but that doesn't mean the author is assuming that these are the only two possible explanations. There are a bajillion trap answers that take this form. They try to make people think that "the only thing mentioned having trait X is therefore the only thing that has trait X". This is the same mistake "All Lives Matter" people make when they hear "Black Lives Matter" and think this claim is somehow saying that "Black lives are the only type of life that matters".

    6% picked this

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