Logical Reasoning

PT129 · S1 · Q12 One can never tell whether another person

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One can never tell whether another person is acting from an ulterior motive; therefore, it is impossible to tell whether someone's action is moral, and so one should evaluate the consequences of an action rather than its morality.

Conclusion

Evaluate the consequences of an action, not its morality ...

Subsidiary Conclusion

.. because it’s impossible to tell whether an action is moral ...

Premise

... since you can’t tell whether an action came from an ulterior motive.

Evaluation

Principle questions are about defining a bridge idea that gets you from the Premise to the Conclusion. Since this argument contains two different conclusions, signified by ‘therefore’ and ‘so’, we can prepare two bridge ideas. One of them gets us from Prem to Subsid Conc, the other from Subsid to Main Conc.

Don’t know motive -> can’t judge moral -> should eval conseq

Goal

We can look for an answer that gets at this move:

Or there could be an answer that gets at this move:

12.

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

  1. Correct

    The intention of an action

    Why this is right

    Intention = motive. Indispensable = required. If we express A in conditional logic, it’s saying “If you don’t have intention, you don’t have evaluation of morality”. That mimics the move from Premise to Subsidiary Conclusion: “if you don’t know true motive, it’s impossible to judge morality of an action.”

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

    50% picked this

  2. The assigning of praise and

    Out of Scope: ‘praise’ / ‘blame’ / ‘value’.

    The conversation is about whether we should evaluate morality or consequences. You can evaluate the morality of an action without going on to praise or blame someone. And an action can have value, apart from whether it has moral value. If we applied this answer's language structure correctly to the argument it would sound like “The knowability of motive is what is most important in assessing morality”.

    2% picked this

  3. One can sometimes know one's

    Trap

    Too Weak / Out of Scope: "knowing your own motives". Beyond being far too weak to be correct on Principle-Justify, this answer pulls in an out of scope idea about “knowing your own motives”, rather than “knowing whether another person’s motive was ulterior”.

    1% picked this

  4. There can be good actions

    Trap

    Too Weak / Out of Scope: "good person" Beyond being far too weak to be correct on Principle-Justify, this answer pulls in an out of scope idea about “a good person”, rather than “a good action”.

    11% picked this

  5. One cannot know whether someone

    Bad Premise Match

    Bad Premise Match: Don't know consequences → don't know morality The author said “If you don’t know the motive of an action, don’t know morality”. This doesn’t match either of the moves the author made.

    36% picked this

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