Logical Reasoning

PT119 · S2 · Q14 Roger Bacon, the thirteenth-century

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Roger Bacon, the thirteenth-century scientist, is said to have made important discoveries in optics.

Conclusion

Bacon's work on optics should be generally disregarded

Evidence

His behavior contradicts his statements: he said that we shouldn't rely uncritically on the opinions of authorities, but he appealed to authority when it suited him.

Evaluation

Sorry, what does that have to do with his work on optics? Isn't optics just a mathematical science that studies the geometry of light rays?

What does his supposed hypocrisy when it comes to appealing to authority have to do with the legitimacy of his work on optics?

This is a famous flaw called Ad Hominem, in which a point of view is discredited because the source has some vested interest in what they're saying or because their past behavior/statements conflict with the present.

Goal

Look for something calling out the Ad Hominem flaw (attacking the source of ideas instead of the ideas themselves) or something otherwise arguing that the work on optics could still be valuable even if Bacon was a raging hypocrite.

14.

The reasoning in the argument is flawed because the argument

  1. presumes, without providing justification, that

    Out of Scope

    It's irrelevant to this author whether authority opinion is often wrong, usually wrong, seldom wrong, etc. The author only brings up authority opinion to demonstrate that Bacon has acted in an apparently hypocritical way. Then she argues that his hypocrisy disqualifies his work on optics.

    4% picked this

  2. attacks Bacon’s uncritical reliance on

    Not a Flaw

    We're not mad at this author for holding Bacon to the same standard Bacon holds others: don't uncritically rely on authority opinion. We're mad at this author because she thinks we should throw Bacon's optics work in the trash, just because he was inconsistent when it came to relying on authority.

    7% picked this

  3. uses Bacon’s remarks to his

    Not a Flaw

    How dare our author treat Bacon's remarks as though they're evidence of his opinions. Just kidding. That's a normal thing to do, unless there's some extenuating circumstance that would make us think he was saying things to his students that weren't his actual opinions

    7% picked this

  4. ignores the fact that thirteenth-century

    Not an Objection

    This would only help the author's position that we should throw away Bacon's work on optics. He's a hypocrite and it's old science that wouldn't hold up nowadays.

    0% picked this

  5. Correct

    criticizes Bacon’s character in order

    Why this is right

    The author does criticize Bacon's character: he told his students X, but nevertheless he did not-X whenever it was convenient for him to do so. And this discussion of his hypocrisy in the evidence is used in order to draw a conclusion that diminishes his scientific findings (his work on optics).

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

    82% picked this

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