PT F97.S1.Q18 – Roseville Courthouse

We are asked to identify the point at issue / disagreement between Mayor Tyler and Councillor Simon. Tyler suggested to build a new courthouse for the city of Roseville in 1982 for a price of 26 million dollars, but ‘now’ in 1992 the price of the courthouse is 30 million. Tyler uses these premises to infer that Roseville would have saved 4 million dollars if the courthouse had been built in 1982, as suggested. Tyler also mentions in passing that the existing courthouse has been overcrowded.

Simon responds by bringing in the topic of inflation: The 26 million dollars that the courthouse would have costed in 1982 are equivalent to 37 million in 1992 dollars. Simon takes this to show that Roseville actually saved money by not building the courthouse. Simon also mentions in passing that the courthouse, had it actually been built, would have been underutilized.

There thus are at least two disagreements in this exchange, one much more overt than the other: (1) Roseville was right not to build the courthouse in 1982: Tyler disagrees, Simon agrees. (2) Had the courthouse been built, it would have been put to good use: Tyler agrees, Simon disagrees. The answer choices are tricky in that four of them purport to get at this first disagreement while not actually resolving it. Only one answer choice, the correct one, gets at the second disagreement and actually resolves it:

(A) This gets at Roseville’s actions going forward, does not directly relate to either disagreement.

(B) This gets at the issue of inflation adjusted prices, does not directly relate to either disagreement.

(C) This gets at the extent of Tyler’s responsibility, does not directly relate to either disagreement.

(D) This does get at the second disagreement and points out one issue where Tyler and Simon disagree: Would a new courthouse actually have been needed / been put to good use? Tyler agrees, as Tyler proclaims the present courthouse overcrowded, i.e. insufficient to serve Roseville’s existing population spatially. Simon disagrees; states that a hypothetical larger courthouse would have remained underutilized. The disagreement is subtle, but definitely present.

(E) This confuses the issue of inflation adjustment with financial upkeep, purports to get at the first disagreement but actually misrepresents information from the passage, in an apparent attempt to confuse test takers who did not select one of the previous answers the first time around.

Takeaway: This is a tricky question in that there are two disagreements only one of which gets resolved. The question stem arguably hints at this by speaking of ‘A point of disagreement,’ rather than of ‘The point of disagreement;’ i.e. the question stem leaves open the possibility of multiple disagreements. Nevertheless, this question demands some reflection. Read stimulus and answer choices more than once to get at the nuance of the issues at play. Do process of elimination for the wrong answer choices. If necessary, flag the question the first time around and return to it at the end of the section.

The reason why the restorers want to make an exception for De Volterra is that De Volterra removed ALL layers of paint in the sections of the paintings where he made his addition before he made these additional. This suggests: De Volterra removed not only those layers of paint that people other than Michelangelo had added but also parts of Michelangelo's works themselves. This in turn means: If De Volterra's additions were removed as well, Michelangelo's underlying painting would not be revealed. Instead, there would just be a blank piece of wall, as De Volterra already removed those sections of Michelangelo's work that were there originally.

Making an exception for De Volterra thus arguably makes sense, because even an addition made by a painter other than Michelangelo would seem better than just have a blank piece of wall in the middle of Michelangelo's painting.

PT16.S3.12 – Retina Scanners

This argument deals with retina scanners, machines that scan the blood vessel patterns in people’s eyes and stores these patterns, such that the scanners can recognized previously scanned patterns. The author furthermore posits that no two eyes have identical blood pattern vessels in their retinas, which seems to suggest that any given person has at least two such patterns, one for the left eye and one for the right one. The author then infers the conclusion that “[a] retina scanner can therefore be used successfully to determine for any person whether it has ever scanned a retina of that person before.”

We are supposed to identify a necessary assumption for this argument, i.e. an assumption that must be true for the conclusion to follow from the premises. Under timed conditions, I chose (B), which posits that everyone’s left and right eyes have identical patterns. I took this to be necessary for the conclusion to follow, due to conclusion’s scope (the conclusion is about “for any PERSON who ever had a retina scanned,” not about “for any given RETINA that ever has been scanned”). However, (B) seems to be false, for at least two reasons: (1) (B) goes against the information we get in the stimulus, where we are explicitly told that no two retinas have identical patterns. (2) (B) does not seem necessary for the rest of the claim that the conclusion seeks to establish (“Retina scanners allow you to answer the question, has one of the this person’s retinas ever been scanned?”). To make (B) a necessary condition, the conclusion would have to say something like “Even if you only scanned one of this person’s two retinas beforehand but not the other, retina scanners allow you to determine whether either of this person’s retinas has ever been scanned before.” However, (B) is not necessary for the way the conclusion is actually stated; the conclusion never says that the evidence to consider for any given person is a scan of only one of their retinas, as opposed to two.

The right answer choice (A) avoids this mistake by blocking another possible objection: What if people’s retina patterns change over time? Wouldn’t this make it impossible to recognize past scans later on, contrary to the argument’s conclusion suggests? (A) blocks this possible objection by establishing: Even if people get e.g. eye sicknesses, the patterns in their retinas remain unchanged over time.

I personally find this the hardest LR question in PT 14; it is (1) bizarre on the level of content, (2) very long and overloads test takers with information, and (3) at the very end of the fourth section, thus hitting you at a point of the test where you already spent 2+ hours intensively thinking about stuff and are mentally exhausted.

In paraphrased form, the stimulus says:

(1) Phenomenon: In the Peruvian desert, there are different sets of lines in the sand. These lines occur in different layers: On the top layer, there are lines that branch out from a single point. Beneath that, there are lines that form a bird figure.

(2) Hypothesis: An investigator argues for the conclusion that both of these sets of lines were brought about by aliens, who supposedly used the Peruvian desert to land their space ships. To support this conclusion, the investigator evokes the premises that the lines in the sand would have been useless to Incas.

The first thing to do here is to figure out what the stimulus is even about: The phenomenon itself is not immediately clear – it is crucial to note that there are TWO sets of lines, not just one –, and the investigator’s hypothesis is counterintuitive to a degree that it becomes all too easy to disregard the glaring selective attention fallacy in their reasoning (Aliens or Incas, not Incas; therefore aliens). So the first hurdle here is to even figure out what is going on, and to throw out one’s common sense intuitions out of the window (How can you even identify the different layers of ancient lines in the sand? How did the lines stick around for so long? All of these questions become irrelevant).

The next hurdle then is the question stem, which again seems bizarre: Here, the test writers tell us that we seek to establish the conclusion that the lines are supposed to refer to astronomical phenomena, and that we are supposed to block an alternative hypothesis to the effect that the lines are non-astronomical. So at this point this seems to become a sort of strengthen question. The question stem is unusual to an extent that it becomes hard to pre-phrase or anticipate how a right answer might look like. Thus process of elimination seems to be the best approach:

(A) North American natives arranged stones in ways that allow for the measurement of astronomical phenomena. This seems to strengthen a little bit in that it points out a seemingly analogous case (It is not only in South America but also in North America that people used geological means to keep track of astronomical phenomena). However, it seems unclear how this answer choice would also have the blocking effect that the question stem is asking for. Thus keep around as a candidate but expect that one of the other answer choices might well be better.

(B) The straight lines indicate positions at which astronomical events could have been observed ‘at plausible dates,’ and the bird lines could represent a constellation. This gets at both sets of lines and associates both of them with astronomical phenomena. The answer thus is fairly specific. Furthermore, the answer itself postulates its own plausibility (‘plausible dates’), which seems like a massive hint, though again unusual. Like the rest of this question, (B) thus again seems wildly counterintuitive, but in the scenario we are supposed to explain, (B) arguably makes the most sense. In particular, (B) approximates the desired function more than (A). Thus far this thus is the least bad answer choice.

(C) The lines form patterns. This answer choice is worse than (B), due to its lack of specificity and its apparent disconnect from the question stem. Worst answer choice thus far.

(D) Central American Natives used rocks to measure astronomical phenomena. This answer choice seems almost identical to (A) and thus provides good grounds to dismiss both (A) and (D): There can only be one correct answer choice, two virtually identical answer choices thus are likely to both be false.

(E) The bird lines might be older than the straight lines. Again irrelevant; (B) must be right.

Takeaways: This seems to be a question where the LSAT really tries hard to make test takers focus exclusively on reasoning structures, not on common sense intuition or plausibility. In this sense, the question is similar to other early LR questions that seem weird content wise but make syntactical sense on the level of formal logic. Focus on getting a clear understanding of what is going on in the stimulus and the question stem; I spent four minutes on this and still felt overwhelmed. Get a clear grasp of what the phenomenon is, what the explanation attempt from the stimulus is trying to say, and how the two alternative explanatory directions from the question stem relate to another. Then use process of elimination to get through the answers.

Conservative: Socialists study history, and they do so to identify trends that inevitably lead to a socialist future. However, this undertaking is certain to fail, because it is only retroactively that historical trends appear inevitable.

Socialist: Socialists do indeed study history, but the purpose of this is practical rather than theoretical: Instead of trying to identify historical trends that themselves bring about socialism, socialists try to identify trends that inform the kind of work that socialists need to do to bring socialism about. Socialism thus is not the inevitable outcome of historical trends, it instead must be worked towards and deliberately brought about.

Under timed conditions this Point at Issue / Disagreement question had me genuinely confused: The conservative and the socialist agree in maintaining that socialists study historical trends, but they disagree about the purpose that these studies are supposed to serve: According to the conservative, these studies are a purely theoretical undertaking, the socialist deems them practical. This thus would have been the issue to anticipate.

The pertinent answer choices are (A) (“[A] socialist society is the inevitable consequence of historical trends that can be identified by an analysis of history”) and (E) (“Socialists analyze history in order to support the view that socialism is inevitable”).

In the case of (E), we do get at a version of the anticipated answer; (E) gets at the conservative’s portraying socialist analyses of history as purely theoretical undertakings, which the socialist rejects.

(A) is more tricky. If (A) said “Socialists believe that a socialist society is the inevitable consequence of historical trends that can be studied,” this arguably would be a right answer choice: The conservative does ascribe this view to socialists, the socialist does not. However, (A) is a claim in itself, not only a belief that socialists may or may not endorse. In this context, the situation is more straightforward: We have no reason to think that the conservative deems the creation of socialist societies inevitable, and the socialist explicitly denies that they are inevitable. So as it stands, the speakers actually seem to agree that (A) is false. This thus can’t be the point at issue.

Takeaways: It is crucial to distinguish clearly between the two viewpoints here, as well as between facts and beliefs. Do not interpret (A) as a belief that the conservative ascribes to socialists; it is rather a claim that the speakers themselves are supposed to endorse or reject.

(1) Most profitable investment: The rate of inflation EXCEEDS the rate of return by a given percentage (say, x%). That is, in real terms, the investment generates a loss; the inflation rate overcompensates whatever profit is being made here. According to the stimulus, this means that the VALUE of this investment declines by the same percentage (x%) at least. Value thus is presented as a function of profit.

(2) Any other investment – that is, any investment that is LESS profitable than the one described in case #1: The value of this investment declines by MORE than x% – that is, the differential between the inflation rate and the rate of return must be even greater than in case #1. Inflation overcompensates the rate of returns even more than in the first case.

Answer choice (C) suggests: The second investment (any investment that is not the most profitable one) is LESS profitable than the most profitable one. If VALUE is a function of PROFIT, and if VALUE in the second case declines more than in the first case, then the second case cannot describe the maximally profitable investment described in case #1.

I’m not sure I’m getting either the economics or the logic behind this right, but it seems to me that a lot of the information presented in the passage is redundant. To conclude what answer choice (C) says ("Case #2 does not describe the most profitable investment"), we only would have needed to know (1) that case #1 is the most profitable investment, and (2) that case #2 can be distinguished from that investment. Is this right / is there a more efficient way to solve this, especially under timed conditions?

Is the idea that this is a one premise argument where answer choice (A) just contraposes to the desired conclusion? That is, are we to assume that "All rich farmers are dishonest" and "Every honest farmer is poor" are logically equivalent, and that "Every honest farmer is poor" thus serves as a sufficient assumption for "All rich farmers are dishonest?"

Why is (E) the right answer choice here, as opposed to (B)?

Stabilizers: Cheap, preserve consistency, but bad for flavor

Low temperatures: Expensive, preserve consistency, better for flavor

(B) suggests: To save money, we should omit the very low temperatures; just use stabilizers to preserve consistency and don't worry about the flavor

Is the idea that the stimulus just remains neutral on flavor, contrary to what (B) suggests?

The stimulus certainly seems to entail the suggestion that cost considerations would encourage ice cream producers to accept higher temperatures, but the stimulus does not also seem to entail an unequivocal recommendation concerning stabilizer use: Contrary to what (B) suggests, ice cream producers might not use very low temperatures (thus reducing costs) AND also not use stabilizers, thus sacrificing consistency for the sake of flavor.

I assume this must be it: The cost considerations mentioned in the stimulus certainly incentivize higher temperatures, but the stimulus does not also entail an unequivocal recommendation concerning stabilizer use. (B) thus does not follow, unlike (E).

Based on an examination of three types of rates (small, average size, and large), a recent study found that in rats, SIZE↑ correlates with HEART PROBLEMS↓. In other words, the study found that the greater a rat is, the less likely it is to have heart problems.

RRE EXCEPT. Four of the answer choices must be able to CONTRIBUTE to an explanation of this correlation; one does not. I did not do a pre-phrase here and went straight to the answers.

(A) Compared to large rats, smaller rats are more likely to have fatal diseases that strike earlier than heart problems. Under timed conditions, I took this to suggest: Small rats generally are more likely to die before heart disease strikes, so that heart disease will be overrepresented among the surviving small rats. However, this inference does not follow. If small rats tend to die young, the total NUMBER of surviving small rats that gets heart disease might be smaller, but there is no indication that there would be a corresponding increase in the PROPORTION of small rats that gets heart disease. This answer choice thus does not contribute to an explanation the observed correlation and thus must be right.

(B) Small rats are more likely to have blood vessel issues that causally contribute to heart disease. This helps to explain the correlation.

(C) Larger rats have less stress than smaller ones. If you assume that stress is causally related to heart disease, this contributes to an explanation. Under timed conditions, I thought that this assumption was too big of a jump, but compared to (A) this answer choice still is better. (A) does not contribute to an explanation at all, (C) does so if we make an additional assumption that seems fairly plausible from a common-sense perspective.

(D) The most common cause of heart disease in rats also causes them to be small. This explains the observed correlation by identifying a joint cause of small size and heart disease among rats.

(E) Larger rats do more exercises than smaller rats that causally contribute to heart health. This contributes to an explanation.

(C) is right, (A) is wrong. Under timed conditions, I had taken (A) to lead to a sampling bias making smaller rats not afflicted by heart disease less likely to survive such that heart disease becomes overrepresented among the surviving small rats. However, this inference is false. Just because small rats might be more likely to die for reasons other than heart disease, heart disease does not have to afflict a greater proportion of the surviving rats. I made a mistake here in assessing the implications of this answer choice and then switched to (C) because (C) requires an additional assumption to be explanatory ('Stress causes heart disease').

Takeaways: I originally had chosen the right answer (A) but then switched to (C) after mistakenly making the above-described inference. I likely was overthinking (A). I need to keep an open eye for the distinction between NUMBERS and PROPORTIONs. If unsure, close my eyes for a couple of seconds, do some deep breaths, calm down and reflect. I definitely felt uncomfortable in selecting my answer but could not quite identify what went wrong. NUMBERS vs. PROPORTIONs is a crucial distinction here, similar to e.g. POSSIBILITY vs. ACTUALITY, INATE vs. ACQUIRED, or MENTAL STATE vs. REALITY. Be vigilant, stay alert to these commonly used distinctions.

(P1) According to dinosaur fossils, dinosaurs had an oxygen isotope ratio in their bones that suggests that their CORES had roughly the same temperature as their LIMBS.

(P2) Today, cold-blooded animals have much warmer CORES than LIMBS.

(MC) Therefore, dinosaurs were probably warm-blooded.

Weaken

This argument assumes, among other things, that warm-blooded animals, unlike cold-blooded animals, do NOT have much warmer CORES than LIMBS, or some other temperature distribution that deviates even more from the dinosaurs'. To anticipate the right answer, I thus was expecting a weaking option targeting this assumption.

(A) Unlike cold-blooded animals, warm-blooded animals only have SLIGHTLY warmer CORES than LIMBS. This goes in the direction of my pre-phrase but is not very strong. Crucially, it remains more likely that dinosaurs were warm-blooded than that they were cold-blooded, just as the author claims. So this answer choice does not seem to actually weaken, even though it gets at the assumption that the author makes, and that I had identified as the weak point of their argument.

(B) Dinosaur fossils don't actually allow you to do the temperature inference described in (P1). This answer is very unusual in that it attacks a premise rather than the reasoning in the argument. Nevertheless, this answer choice definitely weakens, since it takes away the data about dinosaurs that the author presupposes. Keep this answer choice around but be vigilant; see if a less premise-focused answer choice is available.

(C) About oxygen generally. Does not seem to pertain to the argument.

(D) Body temperatures in small and large animals other than dinosaurs. Does not seem to connect directly to the argument; especially since the stimulus does not identify dinosaurs as either small or large.

(E) Warm-blooded animals are more active and use more oxygen than cold-blooded animals. This again does not seem to relate directly to the argument under consideration.

(C), (D), and (E) turn out to be largely unrelated to the argument in the stimulus, and (A) does not seem to weaken the inference made by the author. This leaves (B) as the only remaining answer choice, and thus (B) must be right.

Nevertheless, (B) feels very much uncomfortable and is unusual. (B) just straight up contradicts information that we get in the stimulus, rather than attacking the author's reasoning. It also seems unusual to have this sort of unexpected answer choice so early in the section; just expecting straightforward questions in (Q1)-(Q10) is too naive.

I originally chose (A) because I got too focused on my anticipation of how the right answer could look like, and thus I neglected (B). Nevertheless, a more careful examination of what (A) and (B) are actually saying would have allowed me to get this question right. I need to stay alert to the details of individual answers and compare them against each other; a more thorough examination between (A) and (B) would have allowed me to see that (A) does not in fact weaken and that (B)'s unusual character does not prevent it from being the right answer here. Read answer choices carefully, compare them against each other, and choose the one that has the fewest problems.

This necessary assumption question discusses the treatment of Chronic Fatigue Syndrome (CFS) with a newly developed drug. CFS is associated with three different symptoms, and we don’t know if these symptoms are the effects of only one virus or of multiple different ones. Tests of the new drug indicate that this drug lessens the severity of all three CFS symptoms. The stimulus takes this to provide evidence to the effect that CFS probably is caused by one single virus, not by multiple different ones.

Pre-phrase / anticipation: We need an assumption to the effect of ‘If a single treatment lessens all of a given syndrome’s symptoms, then it is more likely for this syndrome to be caused by a single virus than by multiple ones.’

The pertinent answer choices are (B) and (D). (B) states: “It is more likely that the new drug counteracts one virus than that it counteracts several viruses.” This matches the consequent in the anticipated assumption but leaves out its antecedent. (B) thus does not make the argument valid and would fall short of being a sufficient assumption. But is (B) necessary? If negated, (B) would indicate that it would be equally likely or even more likely that the new drug affected several viruses. This is not at all what the author is trying to argue and thus would seem to rob their conclusion of any support.

(D) states: “Most syndromes that are characterized by related symptoms are each caused by a single viral infection.” This in itself might be right, and arguably (D) would be a good strengthen answer choice. (D) gets at the conclusion and points out parallel cases where similar correlations have been observed as well. A number of things seem off though: (1) Do we know that the alleviated symptoms in fact are ‘related,’ as this answer choice suggests? We certainly know that they all are effects of one or more causes, but does that also render these effects related to one another? (2) The conclusion in the stimulus takes the results of the experiments with the new drug to provide evidence to the effect that CFS has a single cause, but (D) does not contain a connection to these experiments. Instead, (D) is just making a general claim that arguably strengthens the conclusion in isolation but that does not also connect it to the other parts of the argument.

As an NA answer choice, (B) thus seems better than (D). (B) is essentially saying: In probabilistic terms, the new drug’s acting on three different effects indicates that these three effects likely have a single cause rather than three different ones. By contrast, had the drug only affected two of CFS’s three symptoms, it would have been likely that there are at least two causes for CFS, one virus that triggers two of its symptoms and another virus that triggers the third one. (B) is thus hinting at a sort of appeal to simplicity behind the author's reasoning. The author seems to assume: If two different hypotheses about the causal relationships behind a given correlation are possible, the simpler hypothesis is more likely correct.