PrepTest 127, Section 1, Question 26
Essayist: Common sense, which is always progressing, is(56 more words not shown)
If all of the essayist's(12 more words not shown)
- AAt least some(30 more words not shown)
- BOf the useful(18 more words not shown)
- CThe frequency with(15 more words not shown)
- DEach theory within(16 more words not shown)
- EAt least some(29 more words not shown)
Reading the argument
The essayist gives “common sense” a particular meaning: theories tested over time and found useful. That is not necessarily how we would define the phrase in casual conversation, but it is the definition to use for this question.
On this account, common sense changes. Practical ideas about using a new tool, such as a phone, could become familiar in a way they were not before. More useful theories can replace the old ones. But replacement is gradual, so being familiar and widely accepted does not guarantee that an idea is the most useful one currently available.
Imagine a family continuing to repeat an old piece of advice while a better approach is still slowly becoming known. The old advice could have been useful in the past and still lag behind the new approach now. That illustrates the delay the essayist describes: development of the better theory comes before its full absorption into common sense.
What we’re looking for
The question asks what must be true if we accept all of this. I would focus on the obsolete ideas still present right now. There must be some better alternatives that have not yet fully replaced them.
Working the answers
- A
Not yet being found more useful is different from never becoming part of common sense. A theory might later prove useful enough to be absorbed. The essayist does not identify any new theory that is permanently excluded, so the prediction that at least some will never be absorbed goes beyond the facts.
- B
The passage compares an existing theory with an alternative that proves more useful. It does not generally rank all older theories below all newer ones. An old idea about treating people well, for example, could remain very useful while other ideas are replaced. Age by itself does not establish B's general comparison.
- C
We know absorption is slow, but not that the frequency of new theories causes the delay. Perhaps people simply take time to learn and accept an alternative. C supplies a specific explanation for slow adoption that the essayist has not given.
- D
Some replacement is always occurring, but that does not establish that every individual theory will eventually be replaced. One useful idea could remain indefinitely while other parts of common sense change. D turns an ongoing process affecting some theories into a guaranteed fate for each theory.
- ECorrect
The theories already within common sense have been tested and found useful. Yet some remain there after more useful alternatives have been developed, because absorbing those alternatives takes time. Those remaining older theories are therefore less useful than some theories not yet fully absorbed.
E puts the two stages together: a better theory exists, but the slower process of incorporating it is unfinished. That is why the essayist can say common sense both progresses and still contains obsolete theories. We need a difference in usefulness, not a claim that every older theory is entirely false.
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