Q4 - If a civilization as technologically advanced

[mshinners]

Question Type:
Necessary Assumption

Stimulus Breakdown:
The LSAT has brought up evidence against alien life a little too frequently lately; methinks a conspiracy is afoot. The truth is out there.

In this case, the author argues that any aliens who have cell service and are relatively close to Earth could have found us and contacted us. Since they haven't (an implicit premise), the author feels confident concluding that scientists can rule out the existence of technologically advanced aliens within 50 light years.

Answer Anticipation:
The answer could bring up that implicit premise, but I don't see the LSAT actually giving you a correct answer to the effect of, "Aliens have already contacted us - the conspiracy theorists are right!"

However, there's another shift in language here. The premise states that these aliens ""could"" contact us - in other words, they have the possibility to. The conclusion treats it as a certainty that they would have. Because of this shift, we should look for an answer that states if they could contact us, they would have.

Correct answer:
(D)

Answer choice analysis:
(A) Out of scope. The argument relies on the aliens reaching out to contact us; that should happen whether or not the scientists are looking for this advanced type of life form.

(B) Out of scope/Too strong. First, the aliens we care about are within 50 light years from Earth, making this answer out of scope. Second, if we ignore the scope issue, saying that there's no reason to doubt is too strong - there can be reasons to doubt something that you ultimately decide to be true.

(C) Too strong. This argument does rely on scientists being able to understand that the signal, whatever it is, is a communication from the aliens. But they don't need to be able to fully understand it. After all, you probably know your parents are communicating with you, even though you often don't understand what they're saying!

(D) Bingo! The argument relies on the assumption that if aliens can communicate with us, they will communicate with us. Before that happens, they have to have a desire to do so. If we negate this - Aliens wouldn't want to contact Earth - then the argument falls apart. Though, quite frankly, who could blame them?

(E) Premise booster/too strong. First, the argument already tells us that the aliens would be able to find evidence of intelligent life, making this a premise booster. Second, it's too strong - the aliens wouldn't need to recognize all signs of life; just some signs of life.

Takeaway/Pattern: When most people speak, they don't emphasize words such as "could" and "would" instead focusing on the nouns. On the LSAT, these words convey certainty and logical force, so it's important to focus on them!

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