PrepTest 109, Section 3, Question 22
If relativity theory is correct, no object can(48 more words not shown)
The pattern of reasoning in(15 more words not shown)
- AAccording to a(38 more words not shown)
- BIf the defendant(62 more words not shown)
- CThe human brain(54 more words not shown)
- DAlexander the Great(36 more words not shown)
- EIf the big(54 more words not shown)
Reading the argument
These claims look as though they collide. Before declaring one theory false, notice the limit in the first claim: forward in time.
If relativity is correct, an object cannot move forward in time faster than light. Quantum mechanics predicts a particle that travels faster than light. The author keeps relativity in place and offers two ways out: the prediction about the particle is wrong, or the particle travels backward in time and avoids the forbidden forward case.
We don't need to settle the physics. We need to follow how the author handles the apparent conflict. One account supplies a restriction; another supplies an apparent exception. The conclusion says that, if we retain the first account, either the second account is mistaken or the apparent exception falls outside the restriction.
What we’re looking for
That's the pattern to find in the answers. Look for both the apparent conflict and the two possible resolutions. An argument that merely chooses a more likely explanation, or draws another prediction from the same theory, won't match.
Working the answers
- A
The article rejects one ancestry for English and proposes another based on similarities among languages. It doesn't retain an initial rule and then offer two ways to reconcile an apparently conflicting report with it. A supplies support for a different ancestry; it doesn't organize its conclusion around the original's alternatives.
- B
Being irrational and having a motive are not contradictory. The defendant could be both. The argument then concludes that the defendant is guilty, but neither having a motive nor being irrational proves that the defendant committed the crime. More importantly for this task, the conclusion doesn't preserve a rule and give two possible resolutions of an apparent exception. It asserts guilt outright.
- CCorrect
Modern medicine's limit on surviving without oxygen takes the place of relativity's limit on forward travel. The witness's report of a person surviving a week underground takes the place of the prediction about a faster-than-light particle. Each second claim appears to create a problem for the first.
Now keep the first account. If medicine is right, either the witness is mistaken or the person did not lack oxygen. Perhaps there was an air supply. Being buried underground would then be compatible with the medical limit, just as backward travel would avoid the forward-travel restriction in the original.
The conclusion doesn't decide which alternative happened. It says the apparent conflict must be resolved in one of those two ways while retaining the first account. Both the roles and the conclusion match.
- D
This begins with two proposed burial sites, then uses evidence to favor one. The original does not decide that the particle prediction is more likely wrong than the backward-travel alternative. It leaves the alternatives open, conditional on relativity being correct. Having two possibilities somewhere in an argument isn't enough to match that reasoning.
- E
Both predictions come from the same theory. Expansion now and an eventual end to expansion can both be true because they concern different times. The argument draws a later consequence from that account; it doesn't resolve an apparent clash by saying either another account is mistaken or its case lies outside a restriction.
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