Logical Reasoning

PT132 · S4 · Q15 Jewel collectors, fearing

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Jewel collectors, fearing that their eyes will be deceived by a counterfeit, will not buy a diamond unless the dealer guarantees that it is genuine.

Conclusion (should)

Both jewels should be deemed of equal value.

Evidence

A counterfeit diamond would seem to give just as much aesthetic pleasure as a real diamond, if the naked eye can't distinguish one from the other.

Evaluate / Goal

Since we normally pre-phrase a possible answer on Principle-Justify questions by thinking, "IF premise, THEN conclusion", it seems like we want something like this:

if it gives an equal then should deem amount of aesthetic → it of equal value pleasure

We're only interested in principles that can help us argue that "two things should be deemed equal in value", so if any answer wouldn't help us get to that language, we're not interested.

15.

Which one of the following principles, if valid, most helps to justify the reasoning in the argument above?

  1. Jewel collectors should collect only

    Unrelated to Goal

    This is a rule about which jewels collectors should collect. We need a rule about how jewelers should deem the value of something.

    2% picked this

  2. The value of a jewel

    Bad Premise Match

    This principle is correctly about how do deem a jewel's value, but it should be talking about how much aesthetic pleasure the jewel provides or whether the naked eye can distinguish it from another jewel. The premise had nothing to do with "market demand".

    1% picked this

  3. It should not be assumed

    Unrelated to Goal

    This is a rule that lets you conclude how much aesthetic pleasure you should / shouldn't assume someone gets from a diamond. We need a rule that helps us conclude that a diamond and a virtually identical counterfeit should be deemed of equal value.

    2% picked this

  4. Correct

    The value of a jewel

    Why this is right

    This is correctly a rule about how to determine the value of a jewel (the conclusion), and the basis for that is correctly talking about what was discussed in the premise (aesthetic value). Since the author is implying that counterfeits and genuine diamonds provide the same aesthetic pleasure, according to this rule they would be deemed to have equal value. If aesthetic pleasure is the sole measure of value, then things that provide equivalent aesthetic pleasure would be equivalently valuable.

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

    89% picked this

  5. Jewel collectors should not buy

    Unrelated to Goal

    This is a rule that would help us say that a jewel collector should not buy certain jewels. We need a rule that lets us say that a jewel collector should deem two jewels to be of equal value.

    6% picked this

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