PrepTest 129, Section 3, Question 20
Ethicist: Every moral action is the keeping of(37 more words not shown)
The pattern of reasoning in(15 more words not shown)
- AAll calculators are(29 more words not shown)
- BAll exercise is(27 more words not shown)
- CAll metaphors are(18 more words not shown)
- DAll architecture is(18 more words not shown)
- EAll books are(18 more words not shown)
Reading the argument
Set aside whether we agree with the ethicist's account of morality. We need to follow the categories the argument gives us. Every moral action keeps an agreement, and every act of keeping an agreement secures mutual benefit. Moral actions therefore fall within agreement-keeping, which in turn falls within securing mutual benefit.
We are also given a further fact: some agreement-keeping is not moral. Those cases already secure mutual benefit, because all agreement-keeping does. So those very cases establish the conclusion: some acts securing mutual benefit are not moral.
A geometric comparison can make this easier to see. All squares are rectangles, and all rectangles are quadrilaterals. Some rectangles are not squares. Those nonsquare rectangles are quadrilaterals, so some quadrilaterals are not squares. We carry the same examples into a broader category; we don't assume that every quadrilateral is a rectangle.
What we’re looking for
The parallel argument should preserve that structure: three nested categories, some members of the middle category outside the smallest, and therefore some members of the largest outside the smallest.
Working the answers
- A
Calculators, computers, and automated-reasoning devices start out in the same nested relationship. But the exception is given in the largest category: some automated-reasoning devices are not calculators. The conclusion then says some of those devices are not computers. They could all still be computers that happen not to be calculators. This changes both where the exception begins and which group the conclusion excludes.
- B
Exercise, beneficial things, and things promoting health match the three categories. The premise that some beneficial things are not exercise also matches the middle-category exception. But the conclusion says some exercise does not promote health. That contradicts the initial chain, which puts all exercise among health-promoting things. The parallel conclusion would say some health-promoting things are not exercise.
- C
This reasoning works, but it uses a different arrangement. Metaphors belong to both the comparisons group and the surprising-things group. Some comparisons are not surprising, so those comparisons cannot be metaphors, since every metaphor is surprising.
Unlike the original, C never places all comparisons inside the surprising category. It uses an exception to one property to exclude membership in a group requiring that property. The original transfers known nonmoral agreement-keeping cases into the larger mutual-benefit category.
- D
Architecture, design, and art match the initial nested categories, and some design not being architecture matches the exception. Those nonarchitectural designs would show that some art is not architecture. D instead concludes that some art is not design. Nothing given establishes that: the very examples we know about are designs.
- ECorrect
Books correspond to moral actions, texts to agreement-keeping, and documents to acts securing mutual benefit. All books are texts, and all texts are documents. We then learn that some texts are not books, just as some agreement-keeping is not moral.
Those nonbook texts are documents because every text is a document. Therefore, some documents are not books. It carries the same middle-category exceptions into the largest category while preserving what they are not, exactly as the ethicist does.
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