Here we have an MSS question which we know from the question stem: The statements above, if true, most strongly support which one of the following, assuming that the widely accepted physical theories referred to above are correct?
We should note that the question stem tells us that we will encounter “widely accepted physical theories” in the stimulus, and that we will have to accept them as true in order to find our answer.
We start with a scientific phenomenon: there’s a black hole with a ring of gas orbiting around it. This ring of gas is emitting an x-ray that’s flickering as 450 times per second. You find yourself stopping right about now and wondering what the heck is going on here. Here’s the thing: I don’t know how gas rings emit x-rays, and fortunately, I don’t have to! It’s very easy to get lost in the science of a stimulus like this but if we just take this stimulus sentence by sentence, I promise you we’ll be able to ascertain everything we need to in order to succesfully answer the question.
The second sentence introduces us to the “widely accepted physical theory” referenced in the question stem. We’re told that the rate of flickering (of the x-rays) can best be explained if the ring of gas has a radius of 49 km. The LSAT is doing something tricky here: they are emphasizing the uncertainty of this theory by noting that it’s widely accepted (not universally) and using the phrase “best be explained” instead of something more definite. Here’s the thing: we don’t need to worry about the accuracy of this theory because the question stem tells us that we are “assuming [this theory] is true.”
So let’s look at these first two sentences together: black hole is orbited by ring of gas, x-rays flickering at 450 times per second, and a theory tells us that this means the ring of gas has a radius of 49 km. We already know that for our purposes, this theory is true. Therefore, we can say confidently: the ring of gas has a radius of 49 km.
Ok onto the third sentence. We’re told that the ring of gas could not maintain an orbit so close (i.e. 49 km away) unless the black hole was spinning. Well what does that tell us? The black hole must be spinning! The final sentence is phrased in such a way to suggest that this last piece of information is paradoxical or hard to reconcile with the previous two sentences–but it’s not! Our first two sentences have demonstrated that our ring of gas is 49 km away, and our third sentence tells us that given this proximity, our blackhole is spinning.
This stimulus is confusing because it is very hard to visualize. I’d definitely recommend drawing a diagram if that helps you. But at the end of the day, we have three straightforward, interconnecting facts: a ring of gas is emitting x-rays at a certain rate, that ring of gas must be 49 km away from the black hole (the black hole is at the center of the circle created by our gas ring, and radius is the distance from the center to the edge of a circle), but the gas ring couldn’t be 49 km away unless the black hole is spinning. Our simple, straightforward synthesis of this information is that the black hole, therefore, is spinning!
Answer Choice (A) We don’t know anything about rings of gas with a radius above 49 km. Our final sentence says that our gas ring couldn’t maintain an orbit so close without the black hole spinning. This doesn’t tell us anything about how the black hole would behave if the radius was larger.
Answer Choice (B) We simply know that there is one ring of gas in a stable orbit around a black hole that emits flickering x-rays. We do not have any conditionals here that tell us that this is the only type of ring of gas that emits flickering x-rays.
Correct Answer Choice (C) Great! This matches up with how we synthesized the stimulus. We have clearly outlined how our stimulus supports this answer choice.
Answer Choice (D) We don’t know what causes the black holes to spin. We know that the spinning of the black hole is connected to our gas ring maintaining a close orbit, but we have no information about a causal link between the x-rays and the spinning of the black hole
Answer Choice (E) We know that if a gas ring is orbiting around a black hole at a radius of 49 km, then the black hole is spinning. We don’t know anything about the way that black holes behave when they are orbited by a ring with a larger radius.
We’ve got a most strongly supported question/fill in the blank question which we can deduce from the question stem which reads: Which one of the following most logically completes the argument?
We start out with a statement about humans only being able to live happily in a society where love and friendship are the primary motivators. How touching! But also...confusing! Luckily, we have a way of making sense of this: conditional logic.
This statement translates quite readily into a conditional: Human Happiness →Love+Friendship are Primary Motivators for Actions (L+FPM).
Next we get a statement telling us that economic needs CAN BE satisfied in the absence of this condition. This condition is a referential phrase referring back to the second condition in the last sentence: L+FPM. So all we know is that economic needs being satisfied (ENS) is completely independent of L+FPM. They have no bearing on one another! If L+FPM are not present, we could have ENS, but we also could not. If ENS is present we likewise, cannot conclude anything about L+FPM.
Before we move on, what does this tell us about the relationship between ENS and HH? Well we know that if humans are happy then we are definitely living in a society where love and friendship are the primary motives for actions. We likewise know that if we are NOT living in a society where love and friendship are the primary motives for actions:
- Humans are NOT happy
- Economic needs can possibly be satisfied (remember that L+FPM has no bearing on ENS)
What does this tell us about the relationship between HH and ENS? Well, there isn’t one. At least not one that is proven out by our stimulus! (I don’t know about you but I’m certainly a bit happier when my economic needs can be satisfied but that’s another discussion for another day!) The point is: HH requires L+FPM. L+FPM has no bearing on ENS. From what we know–HH and ENS are not linked in any way. They could coincide, they could not.
Then we get an example of ENS in the absence of L+FPM: a merchant society, where the only thing that motivates action is economic utility. The implication here is that in a merchant society, we can have ENS but L+F are not the primary motivators because only economic utility (EU) motivates actions.
Onto the answers:
Answer Choice (A) Is there a relationship between economic utility and human happiness? No! We know that we need L+F to be primary motives, but this does not prevent there from being other motivations for actions. In order to rule out human happiness, EU cannot be the only motivator (because that would prevent L+F from being motivators).
Answer Choice (B) What did we establish about the link between HH and ENS? There is none! It’s a fallacy! Who needs money??!? Ok again, let’s not get sidetracked. There probably is a common sense link between being able to meet your economic needs and being happy, but as far as this stimulus is concerned–there is no link! Therefore we cannot conclude that this answer choice is correct.
Answer Choice (C) Tough to see any support here. We haven’t heard a peep about family and friends until this AC. I suppose you could see interacting with family and friends as something that would occur in a society where L-F are the primary motivators? We’re going way out on an assumption limb here…let’s scurry back to the safety of our stimulus (ok, I’m sorry for that one).
Correct Answer Choice (D) Remember what we established about the link between HH and ENS? There is none! It doesn’t exist! That’s what D is telling us. We can do one without the other. Not “we will” or “we must,” but it’s possible. There’s no definitive link here.
Answer Choice (E) This answer posits a conditional connection between HH and ENS (/H→/ENS or ENS→HH). As we’ve established, there is no such connection, so this answer is incorrect.
We start with the question stem: Which of the following most accurately expresses the conclusion drawn in the argument? This is a Main Conclusion question.
The author begins by stating that it is technologically possible to build non-polluting hydrogen-fueled cars, but the problem is that there isn't a national system of fuel stations that would provide those cars with fuel. Alright, that does seem like an issue. Without a system of fuel stations to make the cars move, all you have are nonpolluting, hydrogen-efficient paperweights. Let's see what the author has to say about this problem.
The next sentence begins with the word "However," indicating a turn to the author's argument. He claims, "this infrastructure is likely to appear and grow rapidly." Was that referential phrasing? You know the drill, we need to find what the referential phrase is referring to. The infrastructure is the hydrogen car fuel system. So the author is claiming that the hydrogen car fueling systems are likely to appear and grow rapidly. At this point, we have some hints that this claim is the conclusion. We have a Context Indicator (however) + Referential Phrasing (this infrastructure). As a rule of thumb, many main conclusions of Main Conclusion questions will have both. Knowing this, we can proceed to the next sentences and ask if they support the claim that the hydrogen fuel system will appear rapidly. If they do, then we have found our Main Conclusion.
The author proceeds by giving an example of how there were no gas stations at one point, but they quickly sprung up in response to consumer demand. OK, so the author is trying to claim, "Hey, remember how there were no gas stations at one point, and then they appeared after consumers started wanting them? Well, the same thing will happen with Hydrogen fuel stations." Terrible argument? Absolutely. However, our job is not to evaluate the argument; it's to find the Main Conclusion that is supported by other claims. While the gas station example fails to make the author's argument valid, it does mildly support the claim that hydrogen fuel stations will likely appear and grow rapidly. Bingo, we have found our main conclusion: The national system of hydrogen fuel stations is likely to appear and grow rapidly. Now, all we need to do is find an answer choice that expresses the same idea.
Answer Choice (A) is context. The author used the fact that it is technologically possible to build hydrogen-powered cars to introduce the problem presented in Answer Choice B. She then turned to her argument that the fuel stations would appear and grow rapidly.
Answer Choice (B) is also context. The author used (A) to introduce the fact that there was no fueling system for hydrogen-powered cars. Both (A) and (B) set up her argument that the fuel system would appear and grow rapidly.
Answer Choice (C) may be appealing, but if you picked (C), you likely thought that hydrogen fuel systems were the new kind of technology that was developed. Well, that would fulfill the sufficient condition, and you would get the outcome that the infrastructure needed to support that technology (the hydrogen cars) would quickly develop in response to consumer demands. That kind of looks like our main conclusion, but there are multiple problems. First, our conclusion did not take the form of a conditional. Second, this answer choice is way too broad. Our author limited her argument to the fueling infrastructure for hydrogen-powered cars. (C) talks about new technology in general. Third, the author mentions nothing about consumer demands in the conclusion of her argument. While she does talk about consumer demands in the gas station example, her conclusion has little to do with consumers. So this is no good.
Correct Answer Choice (D) is almost word for word what the author says, but it replaces the referential phrasing “this infrastructure” with "the fuel-distribution infrastructure." We've got it.
Answer Choice (E) would strengthen the argument by making the hydrogen stations more similar to the gasoline station example. However, our job isn't to strengthen the argument. It is to find a paraphrase of the main conclusion.