Logical Reasoning

PT129 · S3 · Q20 Ethicist: Every moral action

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Ethicist: Every moral action is the keeping of an agreement, and keeping an agreement is nothing more than an act of securing mutual benefit.

Evidence

Every moral action is the MA → KA keeping of an agreement.

Keeping an agreement is KA → MB nothing more than an act of securing mutual benefit.

Clearly, however, not all KA ↢some↣ ~MA instances of agreement- keeping are moral actions.

Conclusion

Therefore, some acts of MB ↢some↣ ~MA securing mutual benefit are not moral actions.

Evaluate

The conclusion follows logically from the second and third premises.

20.

The pattern of reasoning in which one of the following arguments is most similar to that in the ethicist's argument?

  1. All calculators are kinds of

    Wrong Validity

    All calculators are kinds CAL → COM of All computers are COM → DEV devices for automated reasoning. However, not all DEV ↢some↣ ~CAL devices for automated reasoning are Therefore, some DEV ↢some↣ ~COM devices for automated reasoning are not computers. The conclusion is not a valid inference of the premises. It is however a common, and invalid, inference drawn from the second premise.

    12% picked this

  2. All exercise is beneficial, and

    Wrong Validity

    All exercise is beneficial. E → B All things that are B → PH beneficial promote health. However, not all things B ↢some↣ ~E that are beneficial are forms of exercise. Therefore, some E ↢some↣ ~PH exercise does not promote health. This conclusion negates the inference that could be drawn from the second and third premises.

    9% picked this

  3. All metaphors are comparisons, and

    Wrong Structure

    All metaphors are M → C comparisons. Not all comparisons C ↢some↣ ~S are surprising. However, all metaphors M → S are surprising. Therefore, some C ↢some↣ ~M comparisons are not metaphors. While the conclusion does follow from the second and third premises, the logical structure of this argument does not parallel the stimulus because for several reasons. The two “if/then” statements cannot be combined in this answer. Furthermore, for the “some” statement to match the stimulus it should say that not all comparisons are metaphors.

    2% picked this

  4. All architecture is design and

    Wrong Validity

    All architecture is design. ARC → D All design is art. However, not all design is D → ART architecture. Therefore, some art is not D ↢some↣ ~ARC design. The conclusion is not a valid inference of the premises. It is however a common, and invalid, inference drawn from the second premise.

    8% picked this

  5. Correct

    All books are texts, and

    Why this is right

    All books are texts. B → T All texts are T → D documents. However, not all texts T ↢some↣ ~B are books. Therefore, some D ↢some↣ ~B documents are not books. The conclusion follows logically from the second and third premises.

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

    68% picked this

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