#10 - Recently, photons and neutrinos emitted by a distant

[Administrator]

Complete Question Explanation

Strengthen. The correct answer choice is (B)

Although the physics behind this phenomenon may be quite complex, the author’s argument is very
simple. If photons and neutrinos from a distant explosion arrived at Earth at the same time, there is
evidence that they traveled through curved space. If the space through which they travel is curved,
then Einstein’s claim that gravity is a property of space itself is supported. The author’s conclusion
that Einstein is correct – that gravity is a property of space itself – must be strengthened by the correct
answer choice.

Answer choice (A): This answer choice may lend Einstein some credibility, but keep in mind that the
correct answer choice should not simply supply additional information to help validate Einstein’s claims,
but rather should strengthen the main conclusion of the argument (that gravity is a property of space
itself). While it may be true that Einstein’s prediction in answer choice (A) has been found to be correct,
that does not mean that the rest of his theory is correct (alternative explanations could still exist for why
the photons and neutrinos arrived simultaneously).

Answer choice (B): This is the correct answer choice. This answer choice directly strengthens
the reasoning in the stimulus. It states that the only way in which photons and neutrinos emitted
simultaneously by a distant event will reach Earth at the same time is if gravity is a property of space
itself. Since the photons and neutrinos did arrive at virtually the same time, Einstein’s claim (and the
author’s conclusion) must be correct.

Diagrammatically, this answer choice clearly supports the author’s conclusion:

GPS = gravity is a property of space
PNST = photons and neutrinos reach Earth at the same time

Answer choice (B) states: GPS PNST

Contrapositive: PNST GPS

The contrapositive of answer choice (B) shows that, because photons and neutrinos did reach Earth
simultaneously, the conclusion that gravity is a property of space is correct. It is rare that a Strengthen
question will have an answer choice that essentially proves the conclusion to be correct, but test takers
should be aware that this possibility exists and that the correct answer choice will be the one that most
strengthens the argument in the stimulus.

Answer choice (C): If this answer were true, then the mere fact that observers could tell that photons and
neutrinos had arrive at Earth would prove Einstein’s claim incorrect. This is an Opposite answer which
actually weakens the reasoning above and most test takers can quickly classify it as a Loser.

Answer choice (D): Without knowing the predicted impact of Einstein’s claim on subatomic particles
besides photons and neutrinos, this answer choice cannot be used to evaluate the reasoning in the
stimulus. It neither strengthens nor weakens the author’s conclusion.

Answer choice (E): Lack of previous empirical evidence of Einstein’s claim does not strengthen the
argument above. Since there could be several explanations for the lack of evidence besides a flaw in
Einstein’s theory (such as technological limitations), this answer also does not suggest that the author’s
conclusion is wrong. Answer choice (E) neither strengthens nor weakens the conclusion.

[jonwg5121]

Hi, I was curious about the reasoning behind #10 and what the strategy is with this strengthen question.

To my understanding, the argument can be summed up as
Photons and Neutrinos reaching Earth at same time-->Gravity is a property of space itself.

I was able to get (B) because I was able to eliminate all the other answer choices but why is (B) correct?

(B) essentially states ~Gravity is a property of space itself-->~Photons and Neutrinos reaching Earth at the same time. It is the contrapositive of the argument. Can the contrapositive of the argument be a way to strengthen an argument?

[David Boyle]

Hi, I was curious about the reasoning behind #10 and what the strategy is with this strengthen question.

To my understanding, the argument can be summed up as
Photons and Neutrinos reaching Earth at same time-->Gravity is a property of space itself.

I was able to get (B) because I was able to eliminate all the other answer choices but why is (B) correct?

(B) essentially states ~Gravity is a property of space itself-->~Photons and Neutrinos reaching Earth at the same time. It is the contrapositive of the argument. Can the contrapositive of the argument be a way to strengthen an argument?

Hello jonwg5121,

That is a good way to put it. The contrapositive of the argument is indeed "a way to strengthen an argument", since it is the argument!
E.g., if I want to prove "All chickens eat blueberry ice cream", some mild proof might be, "The Chicken Bureau's extensive research shows that a million chickens surveyed all eat blueberry ice cream." If you want something more definitive, though, a statement like, "If something does not eat blueberry ice cream, it is not a chicken" would give full proof that all chickens (if any chickens exist...) do eat blueberry ice cream. Of course, the most recent statement I gave is the contrapositive of the first one.
The LSAT often does this: it uses the contrapositive as the "proof" of an argument--and it always works, because it is just the argument itself, reversed and negated!! What else could you ask for.

Hope this helps,
David