LSAT 90 - Section 4 - Question 20

This is a Point at Issue/Disagreement question.

The question stem says the dialogue provides the most evidence that they disagree. Because of the words “most evidence,” I am getting the sense that the disagreement is not going to be textual, but rather inferred.

I found this question challenging, and if you did as well, I would recommend using an approach we use in comparative passages in Reading Comprehension. For these passages, I read Passage A and take a pass at the answers, then read Passage B and take another pass at the answers. I tend to not do this for Disagreement questions because they are shorter, but there is obviously a spectrum. On one end are the complicated comparative passages, and on the other end, maybe a Disagreement question where each speaker only says one sentence. Perhaps this question falls on the simpler side of the spectrum for you, but if not, I recommend siloing the information. So let's just read Paula’s claim first and take a pass at the answers.

Paula says earthlike planets seem to be the rule rather than the exception, so there are probably intelligent beings on other planets. Furthermore, we can expect our radio telescopes to detect signs of such beings. This is our main conclusion, but there is a huge jump here. Just because there are intelligent beings does not mean that we can detect them, let alone by radio telescopes.

She addresses these points in the following claims. Alien scientists would have basically the same understanding of math and physics that humans have. She does not tell us why they would, but if I accept this premise, I suppose the following subconclusion becomes a bit easier to swallow. She says the alien scientists would thus inevitably discover gravity, electromagnetism, and other fundamental physical phenomena and then develop technologies such as radio communication. Gravity and electromagnetism are consequences of our understanding of math and physics. So over time, I guess one can say alien scientists would discover these physical phenomena and develop technologies based on them. But ultimately, that aliens would develop radio communication is a subconclusion used to support the main conclusion that we can expect our radio telescopes to detect signs of intelligent beings.

Let’s now evaluate the answers. Paula has to either agree or disagree with each of these answer choices, i.e., she has to support it or anti-support it. Any answer choice that Paula has expressed no opinion on is unsupported and immediately wrong.

Answer Choice (A) says they disagree about whether it is probable that there are intelligent alien beings who have developed radio communication. Paula says there probably are intelligent alien beings, and that alien scientists would have developed radio communication. If we combine the two claims, we can say it is probable that there are intelligent alien beings who have developed radio communication. (A) is supported.

Answer Choice (B) says they disagree about whether it is probable that there are intelligent alien beings who have the same legal or political systems that humans do. Paula did not say anything about legal or political systems, so this is unsupported. That means we can eliminate this answer.

Answer Choice (C) says they disagree about whether our technology is influenced by our cognitive makeup. You might be tempted to say Paula disagrees with this. Maybe she believes alien scientists would have the same understanding of math and physics as us because there is something objective and absolute about them that does not depend on unique physiology or cognitive makeup. And our technology depends on math and physics, so it is not influenced by physiology or cognitive makeup.

But remember that Paula did not explain why alien scientists have the same understanding of math and physics as humans. She could believe this is so because aliens have the same physiology or cognitive makeup as humans. You cannot decide between those two possibilities because her statements are consistent with either reading. (C) is unsupported and therefore we can eliminate it.

Answer Choice (D) says they disagree about whether there is likely to be intelligent life on other planets. Paula explicitly says this, so (D) is supported.

Answer Choice (E) says they disagree about whether scientists should spend more time and money on the search for intelligent extraterrestrial life. Paula does not talk about whether the amount of investment into the search for extraterrestrial life is enough. So (E) is unsupported and eliminated.

Let’s now move onto Ashley’s claims. Under timed conditions, you would only evaluate (A) and (D) because you have ruled out (B), (C), and (E) based on Paula’s claims. But since we are reviewing, let’s look at all of them.

Ashley says Paula’s claim is like saying they, the aliens, would inevitably have the same legal or political systems that humans do. Do you detect the sarcasm here? She says our science, math, and technology are unique outgrowths of our physiology, cognitive makeup, and environment. And her conclusion is that using radio telescopes to search for intelligent life is a waste of time and money.

Notice that while Ashley is not committed to whether aliens exist, she is saying that even if they did exist, they would not have the same science, mathematics, and technology as us. Ours are unique, so this implies that aliens would have different ones, just as they would have different legal or political systems if they even had one. And this is why Ashley thinks using radio telescopes to search for intelligent life is a waste of time and money. She does not believe aliens have radio communication.

Answer Choice (A) is anti-supported. Ashley would absolutely disagree that there probably are alien beings who have radio communication.

Answer Choice (D) is unsupported. While Ashley would say radio-communicating intelligent alien beings probably do not exist, everything she says is consistent with her believing that there are or are not some intelligent beings on other planets.

Answer Choice (C) is supported. Ashley believes our technology is a unique outgrowth of our cognitive makeup.

Answer Choice (B) is anti-supported. Ashley is making fun of Paula by talking about aliens who have the same legal or political systems as humans. It is strongly implied that she thinks there are not any.

Answer Choice (E) is unsupported. (E) is talking about general investment into the search for intelligent life. Perhaps Ashley thinks that we should keep searching for aliens, but in some other way.

So from Ashley's perspective, we can get rid of (D) and (E). If you combine the results of both, the only answer choice remaining is the Correct Answer Choice (A). Paula agrees with this. Ashley disagrees with this.