Inability to be tested is a problem for a theory.
Lack of success in explaining why a force is not stronger or weaker is a problem for a theory that tries to explain that force.
A
Superstring theory would be more successful if superstring theorists attempted to explain why the force of gravity is not stronger or weaker than it is.
B
Physical theories that are better established than superstring theory provide better explanations of physical phenomena than does superstring theory.
C
Some physical theory more established than superstring theory has had at least some success in explaining why the force of gravity is not stronger or weaker than it is.
D
A physical theory cannot be true if testing that theory would require us to build a particle accelerator 100 trillion kilometers long.
E
A theory that purports to explain the nature of a force is deficient if it cannot account for the strength of that force.
This is a Principle question.
We are to extract from this argument by analogy the underlying principle. The right answer states the principle, and the argument in the stimulus is an application of that principle.
The argument contains a premise about SUV drivers and a conclusion about cancer and smoking. It’s an argument by analogy. In order for the reasoning by analogy to run through, both the premise and conclusion have to conform to some underlying principle. Otherwise, what happens with drivers and SUVs would have little bearing on cures for cancer and behaviors like smoking.
The premise says that drivers of SUVs have the correct belief that because they're in an SUV, they're better protected. They have lower risk of serious injury. As a result, their behavior changes. Because they know they’re safer, they start to drive more recklessly. They know the negative consequences are not as bad, so they start to take on more risk.
The conclusion says that the discovery of powerful cures for certain high-incidence forms of cancer would probably trigger an increase in behaviors such as smoking and overexposure to sun that are known to increase the risk of such cancers. If we have a cure for lung cancer, then more people would smoke more. If we have a cure for skin cancer, then more people would overexpose themselves to UV light.
Is this analogous to what was described in the premise? Yes, because there is an underlying principle at work here: mitigating or eliminating the negative consequences of an action invites increased participation in that action. Another way to state that is if the risk of harm is decreased, then people will engage more in that form of risky behavior. This unifying principle is what ties together these two totally different situations. It’s how this argument’s reasoning by analogy runs through.
Answer Choice (A) says when people believe that there are several measures they could take to reduce the risk associated with a certain activity, generally they will only take the measure that they believe will most reduce that risk. That’s not the principle at work here.
For the argument to conform to this principle, we’d have to show several measures to reduce the risk associated with driving and then have the driver pick the most effective one. So maybe one measure is to get into an SUV. A second measure is to put on your seatbelt. A third measure is to have airbags. The fourth measure is don't run red lights. According to (A), the principle here is that you assign some probability to each measure and then pick the measure that will most reduce the risk associated with driving.
Correct Answer Choice (B) says the development of ways to protect people from the consequences of behavior that would normally harm them often makes people less careful to avoid such behaviors.
Yes, that’s the principle. “Behaviors that would normally harm them.” What kind of behavior are we talking about here? If applied to driving, then we’re talking about reckless driving. That's behavior that normally would harm you. “The development of ways to protect you from the consequences of reckless driving” is putting you in an SUV. Because when you're in an SUV, it lowers the risk of serious injury as a result of accidents. And as a result, you are less careful to avoid reckless driving.
It’s the same in the conclusion. The behavior that normally would harm people is, say, smoking. If we develop ways to protect people from the consequences of smoking, i.e., lung cancer, then that's going to make people smoke more.
(B) is correct because it extracts the underlying principle that analogizes these two seemingly different situations.
Answer Choice (C) says that people generally take special care to avoid behaviors that they believe would likely lead to serious harm and generally do not take special care to avoid behaviors that they believe will not harm them at all. That’s not the principle at work here.
What behaviors would likely lead to serious harm that people are avoiding? Reckless driving? But if that's the behavior, there's no indication that people are taking special care to avoid reckless driving. What behaviors won't cause harm? The argument doesn’t say. (C) has a hard time mapping onto the argument.
We could make up an argument for (C) to map onto. In general, when traffic lights turn red, everybody stops. When the lights turn green, everybody goes.
This maps onto (C). People are taking special care to avoid behaviors (running a red light) that they believe will likely lead to serious injury. People are not taking special care to avoid behavior that they believe will not harm them (running a green light). In other words, people run green lights.
Answer Choice (D) says people generally exercise more care when performing activities that they know to have risky consequences than when performing activities of unknown risk. That’s not the principle at work here.
To illustrate the principle in (D), consider two activities. Activity one you know is risky. Activity two has a risk profile that’s unknown to you. It could be just as risky, less risky, or more risky than activity one. (D) is saying that people are more careful when performing activity one. This doesn’t map onto the argument.
Moreover, I'm not sure this is a reasonable attitude. If you don't even know the risk profile associated with an activity, wouldn't it be prudent to be extra careful just in case?
Answer Choice (E) says avoiding serious harm to themselves is given a high priority by people in their behavior but avoiding lesser harm is frequently outweighed by various desires. That’s not the principle at work here.
To illustrate the principle in (E), consider the serious harm of losing your arm. You’re going to be very careful to avoid that kind of harm. Now consider the less serious harm of getting a bruise. People regularly choose to risk getting bruised because they have other desires that are more important to them. For example, if you go hiking, you might get bruised. If you play basketball, you might get bruised. The desire to go hiking or play basketball often outweighs the lesser harm of getting a bruise.
If applied to driving, then avoiding serious harm is given a high priority by people in their behavior. That’s why people don’t run red lights. But avoiding less harm is frequently outweighed by various other desires like wanting to get to a destination faster. That’s why people speed. Speeding is not as serious as running a red light, but it does increase your chances of getting hurt (and hurting others).
This is a Principle question.
We are to extract from this argument by analogy the underlying principle. The right answer states the principle, and the argument in the stimulus is an application of that principle.
The argument contains a premise about SUV drivers and a conclusion about cancer and smoking. It’s an argument by analogy. In order for the reasoning by analogy to run through, both the premise and conclusion have to conform to some underlying principle. Otherwise, what happens with drivers and SUVs would have little bearing on cures for cancer and behaviors like smoking.
The premise says that drivers of SUVs have the correct belief that because they're in an SUV, they're better protected. They have lower risk of serious injury. As a result, their behavior changes. Because they know they’re safer, they start to drive more recklessly. They know the negative consequences are not as bad, so they start to take on more risk.
The conclusion says that the discovery of powerful cures for certain high-incidence forms of cancer would probably trigger an increase in behaviors such as smoking and overexposure to sun that are known to increase the risk of such cancers. If we have a cure for lung cancer, then more people would smoke more. If we have a cure for skin cancer, then more people would overexpose themselves to UV light.
Is this analogous to what was described in the premise? Yes, because there is an underlying principle at work here: mitigating or eliminating the negative consequences of an action invites increased participation in that action. Another way to state that is if the risk of harm is decreased, then people will engage more in that form of risky behavior. This unifying principle is what ties together these two totally different situations. It’s how this argument’s reasoning by analogy runs through.
Answer Choice (A) says when people believe that there are several measures they could take to reduce the risk associated with a certain activity, generally they will only take the measure that they believe will most reduce that risk. That’s not the principle at work here.
For the argument to conform to this principle, we’d have to show several measures to reduce the risk associated with driving and then have the driver pick the most effective one. So maybe one measure is to get into an SUV. A second measure is to put on your seatbelt. A third measure is to have airbags. The fourth measure is don't run red lights. According to (A), the principle here is that you assign some probability to each measure and then pick the measure that will most reduce the risk associated with driving.
Correct Answer Choice (B) says the development of ways to protect people from the consequences of behavior that would normally harm them often makes people less careful to avoid such behaviors.
Yes, that’s the principle. “Behaviors that would normally harm them.” What kind of behavior are we talking about here? If applied to driving, then we’re talking about reckless driving. That's behavior that normally would harm you. “The development of ways to protect you from the consequences of reckless driving” is putting you in an SUV. Because when you're in an SUV, it lowers the risk of serious injury as a result of accidents. And as a result, you are less careful to avoid reckless driving.
It’s the same in the conclusion. The behavior that normally would harm people is, say, smoking. If we develop ways to protect people from the consequences of smoking, i.e., lung cancer, then that's going to make people smoke more.
(B) is correct because it extracts the underlying principle that analogizes these two seemingly different situations.
Answer Choice (C) says that people generally take special care to avoid behaviors that they believe would likely lead to serious harm and generally do not take special care to avoid behaviors that they believe will not harm them at all. That’s not the principle at work here.
What behaviors would likely lead to serious harm that people are avoiding? Reckless driving? But if that's the behavior, there's no indication that people are taking special care to avoid reckless driving. What behaviors won't cause harm? The argument doesn’t say. (C) has a hard time mapping onto the argument.
We could make up an argument for (C) to map onto. In general, when traffic lights turn red, everybody stops. When the lights turn green, everybody goes.
This maps onto (C). People are taking special care to avoid behaviors (running a red light) that they believe will likely lead to serious injury. People are not taking special care to avoid behavior that they believe will not harm them (running a green light). In other words, people run green lights.
Answer Choice (D) says people generally exercise more care when performing activities that they know to have risky consequences than when performing activities of unknown risk. That’s not the principle at work here.
To illustrate the principle in (D), consider two activities. Activity one you know is risky. Activity two has a risk profile that’s unknown to you. It could be just as risky, less risky, or more risky than activity one. (D) is saying that people are more careful when performing activity one. This doesn’t map onto the argument.
Moreover, I'm not sure this is a reasonable attitude. If you don't even know the risk profile associated with an activity, wouldn't it be prudent to be extra careful just in case?
Answer Choice (E) says avoiding serious harm to themselves is given a high priority by people in their behavior but avoiding lesser harm is frequently outweighed by various desires. That’s not the principle at work here.
To illustrate the principle in (E), consider the serious harm of losing your arm. You’re going to be very careful to avoid that kind of harm. Now consider the less serious harm of getting a bruise. People regularly choose to risk getting bruised because they have other desires that are more important to them. For example, if you go hiking, you might get bruised. If you play basketball, you might get bruised. The desire to go hiking or play basketball often outweighs the lesser harm of getting a bruise.
If applied to driving, then avoiding serious harm is given a high priority by people in their behavior. That’s why people don’t run red lights. But avoiding less harm is frequently outweighed by various other desires like wanting to get to a destination faster. That’s why people speed. Speeding is not as serious as running a red light, but it does increase your chances of getting hurt (and hurting others).
This is an Inference question.
The question stem says “properly inferred” from the sociologist's perspective. Inference from others' perspective is a question type that we see more often in RC.
The stimulus starts by telling us what rational choice theory says about what causes support for political parties. It says that popular support for political parties is caused by individual voters making deliberate decisions to support those parties whose policies they believe will economically benefit them. In other words, individuals' beliefs about the economic consequences of a particular party's policies cause those individuals to support those parties. This causal relationship is what is meant by “sufficiently explained.”
But the sociologists don't agree. They oppose rational choice theory on the premise that a complex phenomenon like the rise of a political organization or party cannot be caused by a simple phenomenon.
What is this “simple phenomenon”? It must be the individual voters making economic decisions to support political parties, which implies that it must not be a complex phenomenon. This is what Correct Answer Choice (A) says. Sociologists believe that economically motivated decisions by voters need not constitute a complex phenomenon. We are getting hints of an NA question. Note how (A) could have stated this much more strongly. Economically motivated decisions by voters constitute a simple phenomenon. That would have been correct as well. But the test writers took it one step further and stated an inference of that statement.
Answer Choice (B) says a complex phenomenon generally will have many complex causes. This is unsupported. The sociologists only said that a complex phenomenon cannot be caused by a simple phenomenon. This leaves open several possibilities. Perhaps they believe that a complex phenomenon can be caused by many simple phenomena. Or perhaps they believe that a complex phenomenon can be caused by a single complex phenomenon. We’d have to dismiss those alternatives without warrant in order to arrive at (B).
Answer Choice (C) says political phenomena often have religious and cultural causes as well as economic ones. This is even more unsupported. Note the same reasoning in (B) applies here. Additionally, (C) draws an inference to religious and cultural causes on the basis of nothing.
Answer Choice (D) says popular support for political parties is never a complex phenomenon. This is anti-supported. The sociologist called the rise of a political organization a complex phenomenon. Within the context of the stimulus, the rise of the political organization is synonymous with popular support for a political party.
Answer Choice (E) says the decisions of individual voters are not usually influenced by their beliefs about which policies will yield them the greatest economic advantage. This is unsupported. The stimulus talks about a narrow political relationship. It examines the causes of the rise of popular political parties. (E) talks about a much broader political relationship, the causes of individual voting decisions. The stimulus has very little to say about what generally causes (influences) or doesn't cause voters to cast their vote one way or another.
Many sociologists oppose this theory. They oppose this theory based on the premise that a complex phenomenon — such as the popularity of political parties — cannot be caused by a simple phenomenon.
A
economically motivated decisions by voters need not constitute a complex phenomenon
B
a complex phenomenon generally will have many complex causes
C
political phenomena often have religious and cultural causes as well as economic ones
D
popular support for political parties is never a complex phenomenon
E
the decisions of individual voters are not usually influenced by their beliefs about which policies will yield them the greatest economic advantage
This is an Inference question.
The question stem says “properly inferred” from the sociologist's perspective. Inference from others' perspective is a question type that we see more often in RC.
The stimulus starts by telling us what rational choice theory says about what causes support for political parties. It says that popular support for political parties is caused by individual voters making deliberate decisions to support those parties whose policies they believe will economically benefit them. In other words, individuals' beliefs about the economic consequences of a particular party's policies cause those individuals to support those parties. This causal relationship is what is meant by “sufficiently explained.”
But the sociologists don't agree. They oppose rational choice theory on the premise that a complex phenomenon like the rise of a political organization or party cannot be caused by a simple phenomenon.
What is this “simple phenomenon”? It must be the individual voters making economic decisions to support political parties, which implies that it must not be a complex phenomenon. This is what Correct Answer Choice (A) says. Sociologists believe that economically motivated decisions by voters need not constitute a complex phenomenon. We are getting hints of an NA question. Note how (A) could have stated this much more strongly. Economically motivated decisions by voters constitute a simple phenomenon. That would have been correct as well. But the test writers took it one step further and stated an inference of that statement.
Answer Choice (B) says a complex phenomenon generally will have many complex causes. This is unsupported. The sociologists only said that a complex phenomenon cannot be caused by a simple phenomenon. This leaves open several possibilities. Perhaps they believe that a complex phenomenon can be caused by many simple phenomena. Or perhaps they believe that a complex phenomenon can be caused by a single complex phenomenon. We’d have to dismiss those alternatives without warrant in order to arrive at (B).
Answer Choice (C) says political phenomena often have religious and cultural causes as well as economic ones. This is even more unsupported. Note the same reasoning in (B) applies here. Additionally, (C) draws an inference to religious and cultural causes on the basis of nothing.
Answer Choice (D) says popular support for political parties is never a complex phenomenon. This is anti-supported. The sociologist called the rise of a political organization a complex phenomenon. Within the context of the stimulus, the rise of the political organization is synonymous with popular support for a political party.
Answer Choice (E) says the decisions of individual voters are not usually influenced by their beliefs about which policies will yield them the greatest economic advantage. This is unsupported. The stimulus talks about a narrow political relationship. It examines the causes of the rise of popular political parties. (E) talks about a much broader political relationship, the causes of individual voting decisions. The stimulus has very little to say about what generally causes (influences) or doesn't cause voters to cast their vote one way or another.
This is a Weaken Except question, so that means four answers cut against assumptions that the argument made.
Usually when you see a Weaken Except question, that means the argument is especially bad because how else can there be so many assumptions for the answers to contradict? This argument is no exception. It really is bad. And it's bad for having made two different types of assumptions. This can be difficult to recognize. Another difficulty is the use of jargon and the reference to ratios. If it's one thing that LSAT students don't like, it's scientific jargon and math. Both are present here.
The first sentence states a causal relationship that occurs on Earth. On Earth, biological activity leads to, i.e., causes, a change in the ratio. So this is my advice about how to overcome the hurdle of jargon and also incidentally the hurdle of “math.” They don't matter. They don't matter because the rest of the argument and all the answer choices consistently reference the same “ratio.” So who cares what the ratio is called? All we need to focus on is the causal relationship, which is that biological activity causes a change in the ratio.
The next sentence tells us that a newly discovered meteorite, a rock, from Mars exhibits ratios found only in terrestrial minerals dating from before the beginning of life on Earth. The sentence takes a bit of parsing to understand. First, you have to understand that terrestrial minerals mean rocks on Earth. So, in other words, the ratio we find in this rock from Mars is similar to the ratio we find in rocks from Earth before there was life on Earth.
Now we get to the conclusion. The author concludes that it's unlikely life occurred on Mars.
I already said there are two different types of assumptions here. One is the assumption of analogy. This argument relies on reasoning by analogy because it assumes that the causal relationship on Earth of biological activity causing a change in the ratio would also be present on Mars. Would it? Mars and Earth are different places and those differences could mean that this causal relationship isn’t analogous. This is what Answer Choice (A) and Answer Choice (B) point out.
Answer Choice (B) says the effects of life on the ratio depend on a number of climatic and environmental factors with regard to which Earth and Mars differ. This is a very straightforward way of disanalogizing Earth and Mars. (B) tells us that biological activity isn't the only cause that's involved in the alteration of the ratio. Other causes matter too, like climatic and environmental factors, and those factors are different between Mars and Earth. So the ratio found in the Mars rock may not indicate the absence of life on Mars after all.
Answer Choice (A) is more subtle than (B) but also works on the argument’s reasoning by analogy. It says life forms that have a different effect on the ratio from that of life forms on Earth could have evolved elsewhere. This means that we shouldn't assume that Earth life forms’ effects on the ratio is universal. That means it's possible that different kinds of life forms could have evolved elsewhere and that those extraterrestrial life forms could have had a different effect on the ratio. This is an indirect way of suggesting that Mars and Earth are disanalogous. (A) is suggesting that if life had evolved on Mars, it's possible that Martian life would have had a different effect on the ratio.
Of the four answers that weaken the argument, these are the two that cut against the argument’s use of reasoning by analogy. They point out dissimilarities between Earth and Mars. (B) does this specifically and explicitly. (A) does this indirectly by suggesting that Earth and other places in general may be crucially dissimilar.
The other two answers that weaken the argument do so by cutting against a different assumption. That’s the assumption that the single Martian rock tells us something about the state of the Martian planet. If you think about it, it might occur to you that Mars is a big place and the meteorite is quite small by comparison. Is it true that the properties of that single rock reveal something about the entire planet? Well, that all depends on what properties of the rock we’re talking about and what characteristics of the planet we’re trying to figure out. In some ways, surely this rock is representative of Mars. But don't assume that it is representative of Mars in all ways. This is what Answer Choice (D) and Answer Choice (E) point out.
Answer Choice (E) says the current ratio on Mars is different from that at the time the meteorite left Mars. That means the ratio in the rock is not representative of the ratio on Mars today. That means this rock is not evidence of what has happened on Mars since it left the planet. Has life evolved in the intervening time? It’s unclear. (E) severely undermines the relevance of the only piece of evidence on which the conclusion is based by declaring the evidence to be chronologically unrepresentative.
Answer Choice (D) says that relatively few terrestrial mineral samples (rocks we find on Earth) contain ratios that would indicate the presence of life. This is a subtler way of calling out the representativeness of the rock from Mars. (D) says that if we looked at the ratios of rocks on Earth, we would find no signs of biological activity. Yet we know there is obviously plenty of biological activity on Earth. Therefore, this method of reasoning, that is, using the ratio found in rocks, is a poor way of figuring out whether there is life on Earth. This suggests that using this kind of reasoning might also lead to a faulty conclusion for Mars. I'm careful to say “suggests” because I recognize that this (meta) argument itself depends on an analogy between Mars and Earth. The crucial similarity assumed is that just like on Earth, even if there was biological activity on Mars, most of the rocks on Mars would not reflect that activity. That means there’s a good chance that this sample, this only piece of evidence we have, would also fail to capture the effects of life on Mars.
As you can see from the way these answers are structured, (B) and (E) are the more explicit refutations of the two assumptions in the argument. (A) and (D) are the subtler counterparts. They merely suggest that the assumptions are questionable.
Correct Answer Choice (C) says the ratio in the rock from Mars is the same as that on the planet as a whole at the time that the rock left Mars. This doesn't hurt the argument. This helps the argument, though only a little. Now we can be sure that this rock was representative of the ratio on Mars as a whole at some point in time. It doesn't guarantee that it's still representative of the ratio on the planet in the intervening time, as (E) points out, but it does at least partially patch up the issue of representativeness.
A
Life forms that have a different effect on the ratio of S-34 to S-32 from that of life forms on Earth could have evolved elsewhere.
B
The effects of life on the ratio of S-34 to S-32 depend on a number of climatic and environmental factors with regard to which Earth and Mars differ.
C
The ratio of S-34 to S-32 in the meteorite is the same as that on Mars as a whole at the time that the material in the meteorite left Mars.
D
Relatively few terrestrial mineral samples contain S-34 and S-32 in the ratio that indicates the presence of biological activity.
E
The current ratio of S-34 to S-32 on Mars is different from that at the time the material in the meteorite left Mars.
Further Explanation
This is a Weaken Except question, so that means four answers cut against assumptions that the argument made.
Usually when you see a Weaken Except question, that means the argument is especially bad because how else can there be so many assumptions for the answers to contradict? This argument is no exception. It really is bad. And it's bad for having made two different types of assumptions. This can be difficult to recognize. Another difficulty is the use of jargon and the reference to ratios. If it's one thing that LSAT students don't like, it's scientific jargon and math. Both are present here.
The first sentence states a causal relationship that occurs on Earth. On Earth, biological activity leads to, i.e., causes, a change in the ratio. So this is my advice about how to overcome the hurdle of jargon and also incidentally the hurdle of “math.” They don't matter. They don't matter because the rest of the argument and all the answer choices consistently reference the same “ratio.” So who cares what the ratio is called? All we need to focus on is the causal relationship, which is that biological activity causes a change in the ratio.
The next sentence tells us that a newly discovered meteorite, a rock, from Mars exhibits ratios found only in terrestrial minerals dating from before the beginning of life on Earth. The sentence takes a bit of parsing to understand. First, you have to understand that terrestrial minerals mean rocks on Earth. So, in other words, the ratio we find in this rock from Mars is similar to the ratio we find in rocks from Earth before there was life on Earth.
Now we get to the conclusion. The author concludes that it's unlikely life occurred on Mars.
I already said there are two different types of assumptions here. One is the assumption of analogy. This argument relies on reasoning by analogy because it assumes that the causal relationship on Earth of biological activity causing a change in the ratio would also be present on Mars. Would it? Mars and Earth are different places and those differences could mean that this causal relationship isn’t analogous. This is what Answer Choice (A) and Answer Choice (B) point out.
Answer Choice (B) says the effects of life on the ratio depend on a number of climatic and environmental factors with regard to which Earth and Mars differ. This is a very straightforward way of disanalogizing Earth and Mars. (B) tells us that biological activity isn't the only cause that's involved in the alteration of the ratio. Other causes matter too, like climatic and environmental factors, and those factors are different between Mars and Earth. So the ratio found in the Mars rock may not indicate the absence of life on Mars after all.
Answer Choice (A) is more subtle than (B) but also works on the argument’s reasoning by analogy. It says life forms that have a different effect on the ratio from that of life forms on Earth could have evolved elsewhere. This means that we shouldn't assume that Earth life forms’ effects on the ratio is universal. That means it's possible that different kinds of life forms could have evolved elsewhere and that those extraterrestrial life forms could have had a different effect on the ratio. This is an indirect way of suggesting that Mars and Earth are disanalogous. (A) is suggesting that if life had evolved on Mars, it's possible that Martian life would have had a different effect on the ratio.
Of the four answers that weaken the argument, these are the two that cut against the argument’s use of reasoning by analogy. They point out dissimilarities between Earth and Mars. (B) does this specifically and explicitly. (A) does this indirectly by suggesting that Earth and other places in general may be crucially dissimilar.
The other two answers that weaken the argument do so by cutting against a different assumption. That’s the assumption that the single Martian rock tells us something about the state of the Martian planet. If you think about it, it might occur to you that Mars is a big place and the meteorite is quite small by comparison. Is it true that the properties of that single rock reveal something about the entire planet? Well, that all depends on what properties of the rock we’re talking about and what characteristics of the planet we’re trying to figure out. In some ways, surely this rock is representative of Mars. But don't assume that it is representative of Mars in all ways. This is what Answer Choice (D) and Answer Choice (E) point out.
Answer Choice (E) says the current ratio on Mars is different from that at the time the meteorite left Mars. That means the ratio in the rock is not representative of the ratio on Mars today. That means this rock is not evidence of what has happened on Mars since it left the planet. Has life evolved in the intervening time? It’s unclear. (E) severely undermines the relevance of the only piece of evidence on which the conclusion is based by declaring the evidence to be chronologically unrepresentative.
Answer Choice (D) says that relatively few terrestrial mineral samples (rocks we find on Earth) contain ratios that would indicate the presence of life. This is a subtler way of calling out the representativeness of the rock from Mars. (D) says that if we looked at the ratios of rocks on Earth, we would find no signs of biological activity. Yet we know there is obviously plenty of biological activity on Earth. Therefore, this method of reasoning, that is, using the ratio found in rocks, is a poor way of figuring out whether there is life on Earth. This suggests that using this kind of reasoning might also lead to a faulty conclusion for Mars. I'm careful to say “suggests” because I recognize that this (meta) argument itself depends on an analogy between Mars and Earth. The crucial similarity assumed is that just like on Earth, even if there was biological activity on Mars, most of the rocks on Mars would not reflect that activity. That means there’s a good chance that this sample, this only piece of evidence we have, would also fail to capture the effects of life on Mars.
As you can see from the way these answers are structured, (B) and (E) are the more explicit refutations of the two assumptions in the argument. (A) and (D) are the subtler counterparts. They merely suggest that the assumptions are questionable.
Correct Answer Choice (C) says the ratio in the rock from Mars is the same as that on the planet as a whole at the time that the rock left Mars. This doesn't hurt the argument. This helps the argument, though only a little. Now we can be sure that this rock was representative of the ratio on Mars as a whole at some point in time. It doesn't guarantee that it's still representative of the ratio on the planet in the intervening time, as (E) points out, but it does at least partially patch up the issue of representativeness.
This is a Flaw/Descriptive Weakening question.
You might be able to figure out the flaw before looking at the answer choices since we're dealing with a repetitive causal logic flaw.
The official says that six months ago, the fines for parking violations on the city’s streets were raised to help pay for the parking garage that had just opened. Since then, parking violations on our streets have dropped by 50 percent. These are our premises, and here comes the conclusion. Hence, if we want there to be even fewer parking violations, the fines should be raised again.
There is an unstated causal assumption. The official makes this recommendation because she assumes that the fines increasing not only coincided with but caused the reduction in parking violations. This could be true, but remember that two things happened: fines were increased and a new parking garage opened. Do we know that it is not the parking garage that caused the reduction? I mean, it's a parking garage. It's for parking cars. I am not saying it has to be, but simply that the official’s reasoning is flawed because she overlooks this. She assumes increased fines —cause→ reduction without considering parking garage —cause→ reduction.
This error can be phrased in a couple of different ways, but let's first look at how it is phrased in the correct answer choice and then play around with alternative phrasings.
Correct Answer Choice (E) says the argument fails to establish that the initial decrease in parking violations was not due to the availability of additional parking spaces (from the newly opened parking garage). This is great. To establish that the argument’s preferred explanation is correct, we have to establish that it is not the alternative explanation that caused the reduction. But like I said, this is not the only way to phrase this flaw. Let’s look at (A).
Answer Choice (A) says the argument takes a possible effect of a reduction to be a possible cause of that reduction. I think one of the reasons why (A) is attractive is that the correct answer could have been phrased similarly to (A). It could have said that the argument takes a possible cause of a reduction to be the definite cause of that reduction. This could have been the correct answer. It would have been using a positive phrasing, "takes a possible cause..." as opposed to the negative phrasing in (E) of “fails to establish...” but that's fine. There are many ways to phrase the error.
But the problem with (A) is that the argument didn't take the effect of the parking violations going down to be the cause of the fines going up. That is, the argument didn't take the loss of revenue from fewer parking violations to be the cause of increased fines.
Answer Choice (B) says the argument takes for granted that raising fines a second time will reduce parking violations at least as much as it did the first time. Takes for granted is also language that the correct answer could have used. The argument "takes for granted that a possible cause of a reduction is the definite cause of that reduction." But, of course, this is not what (B) says. What (B) says is not even descriptively accurate. The official does not say that raising fines will get us another 50 percent reduction. She merely says, “if we want to further reduce,” and does not say by how much.
But (B) is not great even if it passed the descriptive accuracy test. Say we changed (B) and it now reads, “takes for granted that raising fines a second time will reduce parking violations like it did the first time.” This is better since it is a flaw to assume that something will work a second time just because it worked the first time. But (B) still misses the major flaw that it worked the first time.
Answer Choice (C) says the argument fails to take into account the financial benefits the city is now deriving from fines for parking violations. So it did. Okay, (C) is descriptively accurate. But how is this the flaw? Did the official need to talk about these benefits, like how we might use these funds to hire more traffic police or something? This has nothing to do with evaluating the argument.
Answer Choice (D) says the argument takes for granted that people who park their cars illegally would prefer to park their cars legally. Of course people would prefer to park legally. Okay, I know that some people hate being told what to do and believe that it is their right as red-blooded Americans to park on their neighbor's lawn, but the overwhelming majority of people do not.
(D) is indeed an assumption that runs through the whole argument, because whether it is the fines or the new garage that resulted in the reduction, both carry the assumption that people want to park legally. But the best we can do is to say that (D) is descriptively accurate. But it doesn't describe the flaw.
This is a Flaw/Descriptive Weakening question.
You might be able to figure out the flaw before looking at the answer choices since we're dealing with a repetitive causal logic flaw.
The official says that six months ago, the fines for parking violations on the city’s streets were raised to help pay for the parking garage that had just opened. Since then, parking violations on our streets have dropped by 50 percent. These are our premises, and here comes the conclusion. Hence, if we want there to be even fewer parking violations, the fines should be raised again.
There is an unstated causal assumption. The official makes this recommendation because she assumes that the fines increasing not only coincided with but caused the reduction in parking violations. This could be true, but remember that two things happened: fines were increased and a new parking garage opened. Do we know that it is not the parking garage that caused the reduction? I mean, it's a parking garage. It's for parking cars. I am not saying it has to be, but simply that the official’s reasoning is flawed because she overlooks this. She assumes increased fines —cause→ reduction without considering parking garage —cause→ reduction.
This error can be phrased in a couple of different ways, but let's first look at how it is phrased in the correct answer choice and then play around with alternative phrasings.
Correct Answer Choice (E) says the argument fails to establish that the initial decrease in parking violations was not due to the availability of additional parking spaces (from the newly opened parking garage). This is great. To establish that the argument’s preferred explanation is correct, we have to establish that it is not the alternative explanation that caused the reduction. But like I said, this is not the only way to phrase this flaw. Let’s look at (A).
Answer Choice (A) says the argument takes a possible effect of a reduction to be a possible cause of that reduction. I think one of the reasons why (A) is attractive is that the correct answer could have been phrased similarly to (A). It could have said that the argument takes a possible cause of a reduction to be the definite cause of that reduction. This could have been the correct answer. It would have been using a positive phrasing, "takes a possible cause..." as opposed to the negative phrasing in (E) of “fails to establish...” but that's fine. There are many ways to phrase the error.
But the problem with (A) is that the argument didn't take the effect of the parking violations going down to be the cause of the fines going up. That is, the argument didn't take the loss of revenue from fewer parking violations to be the cause of increased fines.
Answer Choice (B) says the argument takes for granted that raising fines a second time will reduce parking violations at least as much as it did the first time. Takes for granted is also language that the correct answer could have used. The argument "takes for granted that a possible cause of a reduction is the definite cause of that reduction." But, of course, this is not what (B) says. What (B) says is not even descriptively accurate. The official does not say that raising fines will get us another 50 percent reduction. She merely says, “if we want to further reduce,” and does not say by how much.
But (B) is not great even if it passed the descriptive accuracy test. Say we changed (B) and it now reads, “takes for granted that raising fines a second time will reduce parking violations like it did the first time.” This is better since it is a flaw to assume that something will work a second time just because it worked the first time. But (B) still misses the major flaw that it worked the first time.
Answer Choice (C) says the argument fails to take into account the financial benefits the city is now deriving from fines for parking violations. So it did. Okay, (C) is descriptively accurate. But how is this the flaw? Did the official need to talk about these benefits, like how we might use these funds to hire more traffic police or something? This has nothing to do with evaluating the argument.
Answer Choice (D) says the argument takes for granted that people who park their cars illegally would prefer to park their cars legally. Of course people would prefer to park legally. Okay, I know that some people hate being told what to do and believe that it is their right as red-blooded Americans to park on their neighbor's lawn, but the overwhelming majority of people do not.
(D) is indeed an assumption that runs through the whole argument, because whether it is the fines or the new garage that resulted in the reduction, both carry the assumption that people want to park legally. But the best we can do is to say that (D) is descriptively accurate. But it doesn't describe the flaw.