PrepTest 101, Section 3, Question 10
All material bodies are divisible into parts, and(23 more words not shown)
The final conclusion above follows(9 more words not shown)
- AEverything divisible is(3 more words not shown)
- BNothing imperfect is(1 more words not shown)
- CThe spirit is(1 more words not shown)
- DThe spirit is(1 more words not shown)
- EThe spirit is(4 more words not shown)
Reading the argument
Think of a material object like a pen: it has a body, ink, and other parts. The passage gives us a rule that all material bodies can be divided into parts, then another rule that everything divisible is imperfect. Given those rules, the first conclusion works. A material body is divisible, so it belongs among the imperfect things.
Then the spirit suddenly appears. What have we been told about it? Nothing. We know what must be true of material bodies, but we haven't been given a fact that puts the spirit inside or outside that group.
To prove that the spirit isn't material, I'd give it a feature that conflicts with a requirement every material body meets. If the spirit were indivisible, it couldn't be one of the material bodies, since they are all divisible. If the spirit were perfect, it couldn't be one of them either, since they are all imperfect. Either fact would separate the spirit from the whole group.
What we’re looking for
The question asks us to make the conclusion follow. Look for one of those conflicts. Don't turn the given rules around: material things must be divisible and imperfect, but we haven't been told that every divisible or imperfect thing is material. Merely giving the spirit one of those features would not establish whether it is a material body.
Working the answers
- A
This adds a rule in the other direction, from divisible things to material bodies. Even with that added connection, we still have no fact about the spirit. It could be a material, divisible, imperfect thing without violating any of the premises. A doesn't exclude that possibility.
- B
This says imperfect things cannot be indivisible: they must be divisible. But what is the spirit like? B never tells us. We could still suppose it is material, divisible, and imperfect, and all the rules would hold. Another rule about the categories doesn't supply the missing fact about the spirit.
- C
Being divisible would place the spirit among the imperfect things under the given rule. It would not prove that the spirit is material, and it would not prove that it isn't. We need a feature that rules out material status; this is a feature every material body already has.
- DCorrect
Every material body is imperfect: material leads to divisible, and divisible leads to imperfect. If the spirit is perfect, it cannot belong to that group. Otherwise, it would have to be both perfect and imperfect. D supplies the incompatible feature we predicted and makes the conclusion follow.
- E
The indivisible option would do the job. But E also allows the spirit to be imperfect, and an imperfect spirit could still be material. For example, a divisible, imperfect spirit would satisfy this answer through its second option without conflicting with any of the premises. Because one permitted possibility leaves the conclusion unproved, the either-or statement isn't enough.
If the choice said indivisible or perfect, either route would exclude the spirit from the material group. It says imperfect instead, and that one prefix changes what we can establish.
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