A is not necessary because whether or not young people are accurate in discerning how fast society is changing doesn't prevent the fact that they will either place much or little value on the advice of elders. We are told when X, then Y. We are not told when young people are accurate in knowing that X is happening, then they do Y.

I've seen this idea come up on other LSAT questions and you have to get in the habit of seeing causal/correlative patterns like this that don't require consciousness of the actors/phenomena.

The flaw becomes more apparent when the answer choices, AC A in particular, are not on your mind. I took a fresh look at this question a few days after answering and it intuitively makes a lot more sense. Think about how strong the conclusion is.

MC: Someone is telling a lie.

Premises:

• Ms. Chan said she retired

• A colleague said that she is working harder than ever and currently on a business trip

Equivocal is a wild word, but it captures the heart of the flaw- what if there is another fact that explains both contradictory statements? The LSAT is all about being skeptical about claims and when we hear a claim as big as the author's in this question, we should have alarms going off in our heads about an unwarranted jump. There are many more possibilities than someone lying here. Also remember, although it seems within the realm of possibility or even perhaps likely that someone is lying, when the author makes that conclusion, they are effectively precluding any other possibility that could explain these events. Do we really have enough information based on the stim to believe that there was no other reason for the contradictory statements? Do we have any evidence that just because Ms. Chan said she retired last year that she couldn't have changed her mind and returned to work somewhere else? No.

The two big loopholes in this argument are 1) what evidence do we have to say that we should take into account a discipline's blemished origins when we assess said discipline's scientific value and 2) does the example of the alchemists bear any relevance to modern chemistry? We are told that landmark results were obtained by alchemists- who were known for XYZ, but does that count as the blemished origins of chemistry? Don't assume so!

A sounds a bit appealing, but its just word drama that plays on the correlation we were exposed to in the stimulus. We already know there is a correlation between bacteria resistant to heavy metal poisoning and bacteria resistant to antibiotics. If we grant A to be true, that most bacteria that are not resistant to antibiotics are not also resistant to heavy-metal poisoning, we are literally still at the same crossroads. The reason is that it tells us NOTHING about CAUSATION. Heavy-metal resistance CAUSING antibiotic resistance is what we are after. Knowing that the two usually do occur together tells us nothing about causation.

This was such a frustrating question. I went back and sat with the stim isolated and it helped me see the gap in reasoning between the premises and conclusion. The premise is that decaf three cup drinkers are twice as likely to develop arthritis as reg 3 cup drinkers. The conclusion is ridiculously strong- decaf 3 coffee must contain an substance that not only causes arthritis, but also that that substance is not present in regular coffee. The majority of the flaw is that all we have is a correlation and not only does the author predict causation, but the author predicts the direction of the causation. The author does not have any evidence to suggest it is the decaf coffee itself (rather than a third factor or even a reverse causal relationship), the author also concludes that the direction is that decaf is positively interacting and causing arthritis when it could be that regular coffee is the positive actor who reduces the risk of arthritis. In that case, it could be possible that decaf doesn't do a thing.

Imagine I have something else that exists as an opposite of the other thing like a gas car and an EV car. Say owners of gas cars are twice as likely to make less than 50K a year than owners of electric cars. Thus, something about the electric car must cause their owners to lose a lot of money. There doesn't have to be any causal relationship between gas cars and their owners' wealth. It could just be that driving an electric car typically is associated with higher paying jobs which cause ownership of the car and the wealth of the driver. It could even be that the electric car somehow causes their owners to be more motivated and make more money so they can pay off their bills. All of this could be true while there is absolutely no causal relationship between the gas car and their owners' wealth.

So, when we have two version of a thing (regular vs. decaf coffee) and they each respectively have a correlation with a phenomenon (arthritis), we cannot assume that one of the things (strange substance in the decaf coffee) causes the phenomenon, because it could be just as likely that the other thing is causally responsible.

For E to be the right answer, the argument would conclude something along the lines of, "thus in order to protect your dog from arthritis, you should never neuter your dog." That would be implying that not neutering means proper bone development and that proper bone development means no arthritis.

As the argument is, E is not a flaw because it is irrelevant to the conclusion. The conclusion is waiting till a dog is full-grown to neuter compared to early puppyhood. In no way does this argument suffer logically from not addressing the fact that a dog with properly developed bones might develop arthritis.

When I think a tricky ac might be a flaw, I grant it truth for a moment as a logic exercise. Say there is a possibility that dogs with properly developed bones can develop arthritis. Is the argument significantly affected by that? No. Where the argument would significantly suffer is if we find out that neutering a dog in middle or late puppyhood or really anytime besides full-grown adulthood is just as effective in arthritis prevention as is neutering after a dog becomes full-grown. then the author can't advance their conclusion.

MC: Crying reduces stress.

• We know this because tears contain hormone X.

• emotional stress produces hormone X.

• Shedding tears reduces hormone X.

Assumption: If crying reduces stress, then the author must be assuming that hormones are causing the stress. How else would crying be connected to the reduction of stress. To identify the flaw and see why E is right, you have to trace back the causal mechanism of crying reduces stress. For crying to reduce stress, the stress hormone has to be reduced supposedly and our evidence only says that shedding tears removes the hormone. So if crying reduces a certain hormone and consequently reduces stress the assumption must be that the hormone is what is causing the stress. If stress or something else is causing the production of the hormone. Then reducing levels of that hormone isn't guaranteed to reduce stress or whatever it is that is actually causing the hormone.

@ramonpeinado that's exactly what I thought to. I negated C and thought that the negated assumption strengthened the argument and actually made it possible. If we are recommending farmers switch to no-till, then there better be a world where there are other viable options besides deep tillage or else why bother prescribing a switch. Then I saw that in the heat of running under time I ignored that we are talking about tilling by another method. By nature, no-till is different from tilling. So C is talking about another method we haven't considered.

Is it reasonable to assume that when AC B talks about overly lenient punishments that it in fact is referring to the stimulus? Yes, absolutely.

The MC is judges shouldn't mitigate based on motives and the support is that motives can be deceitfully presented. What does this suspicion/deception possibility have to do with the argument? This is a loophole or a reasoning gap. The author assumes while motives can be falsely presented that judges or others are indeed falling for the trap and can't discern good from bad motives. One way to help this argument is to patch that up, but the author goes down another path and it still works. We know that the author is talking about overly lenient punishment because well, that's the whole point of talking about a mitigated punishment and a falsely presented motive. A falsely presented motive would yield a punishment that was mitigated for the sake of a motive that actually was not the real motive of the perpetrator. Thus, if we grant B is true and we are told that it would be better to err on the side of overly severe punishment (punishment that will severely punish people with good motives as if they had nefarious ones), than the theorist's MC is strengthened. This is because the MC says we shouldn't go based on motives and D says we should go based on something else. Perfect.

When it comes to telling the difference between A and E, you need to remember that the former is talking about reporting the news (imagine on-air, live reporting) while the other is talking about discerning what to report on (think about the process before reporting where they decide what they can fit in a time slot).

A- Sarah agrees with this when she says they always interpret the news. Doesn't matter if it is the allotting time beforehand or live, on-air recording. If you are a reporter-> you're always interpreting. However, Ramon doesn't say anything about whether reporters do interpret the news when they report. He says they should never, but that doesn't = they currently do interpret when they are reporting. Ramon actually doesn't talk about reporting and interpreting. Ramon says reporters will deem a story to be newsworthy and then they are obligated to relay the facts which is the actual act of reporting. But, as far interpreting goes, Ramon doesn't say whether or not they are doing it when they report. He implies that when they are discerning what to report and what not to, that it isn't interpretation. But, Ramon just doesn't tell us whether reporters are always interpreting. It would be unreasonable to speak on his behalf and say Ramon totally disagrees with AC A. Ramon just says they should not.

A- there isn't a mere coincidence and the conclusion isn't a causal relationship. The conclusion conflates being satisfied with a current percentage with not wanting more money to be spent on the program in the event the total budget increases.

B- We know 90% are happy with the percentage of the budget spent on the program, but then the argument goes out on a whim to say well, if we got all this money, we should spend it elsewhere because people are saying currently, we are happy with the PERCENTAGE of our budget spent. That doesn't mean they don't want more money spent on it eventually. This is correct.

C- This would make more sense if the conclusion was something like since 90% are satisfied with the percentage of the budget spent on the program, about 90% are satisfied with the budget as a whole. The argument isn't implying that they are satisfied with the budget as a whole. The argument claims that if the budget increased, people wouldn't want MORE to be spent. The conflict in this argument is between percentages and amount.

D- The argument totally fails to consider this, but who gives a damn! What does that have to do with whether or not current satisfaction with the percentage spent = future increase should be spent elsewhere

E- the argument isn't saying that more money will or should be spent on a program. It's talking about spending money elsewhere, not on student counseling.

A- Leggett's argument does not show McBride's claims to be contradictory. If it was, Leggett would be only working with the statements McBride makes and then reinterpreting it so point out the controversy within. Leggett's argument instead INTRODUCES a new concern. What if less full-size cars is safer because sub on sub accidents are not as dangerous.

B- Both authors only talking about full-size and subcompact. That doesn't mean they assume that those are the only types of cars. They are just the only ones they talked about.

C- This accurately describes Leggett's method of reasoning. Leggett shifts to a new perspective by which they consider safety when stating how less full-size cars will actually increase safety because sub on sub accidents are less dangerous. This is a new idea that McBride didn't consider.

D- Leggett doesn't criticize the accuracy of McBride's evidence. Leggett introduces a new way to think about it.

E- Where does Leggett even mention what would happen if we went with McBride's argument?

@J.Y.Ping And on the third day, flaw boss Ping rose again to bait us with his toughest flaw demons.

I love it! The example flaws on flaw monster are similar in language to actual questions, but also avoid using actual test questions.

Assumptions: If the fifth universal force would explain the smaller than expected gravitational measurement, that is good enough reason to believe it. The fifth force, while being compatible with the smaller than expected measurement, is also not in conflict with any other aspects of the scientific evidence for the four other forces.

• A)- So what? We don't know how important the role of the equipment is in determining whether or not the fifth force theory is plausible. Also, the four forces theory was believed up until 1986 so the fact that extremely sophisticated equipment was not available till the 70s means that the scientists still could have got their hands on that equipment and measured. Maybe this explains why scientists hadn't found the fifth force till 1986, but still it doesn't strengthen the fifth force theory.

• B- Perfect because it precludes an alternative hypothesis where the fifth force explains the smaller measurement, but is in conflict with every other piece of evidence.

• C- We don't care if it's an aspect of gravity, itself, the moon, or my ass. This has the right buzz words and thus appears to provide the mechanism for how the fifth force might work, but it doesn't actually affect whether or not fifth force is actually true or not. In fact, it might even weaken the argument because it's basically saying the fifth force is not an actual force. It's just the outer layer or trace effect of gravity.

• D- This weakens everything. Oh so the results are just bogus? Weakening the traditional or fifth force theory isn't of any help.

• E- Correlation DOES not imply causation. Whether or not other exciting advancements were happening in science doesn't give us any reason to expect that if you come up with a theory in this time, then it is probably true. Imagine the other version. Because the time at which the theory was posed was a time of scientific depression and darkness, the theory probably holds no ground. What the heck? Why does any correlation with a scientifically dark time mean that a theory from that time should automatically be tossed aside?

This felt more confusing than usual and I think it's because of the way the two premises trigger the conclusion. The conclusion (not true that Alban teaches two intro courses) doesn't sound like the necessary condition of either rule.

• Prof A French Dept-> Max 1 intro

• course next term-> advanced

But the bones are the same and the OVERALL conclusion is as well. The argument concludes it is NOT TRUE that both courses are intro courses. Each rule indepdently arrives at a similar conclusion. It won't be true that Prof A's courses will both be advanced because if you are teaching in that department it is necessary that you teach a maximum of one intro course. The other premise triggers the same conclusion. Any language course next year will be advanced. Thus, the conclusion is true. It cannot be that both of Alban's courses are intro because if Alban is teaching a language course, it is necessary that it is advanced.

I went into this question pre-phrasing an NA that sounded like there are no birds with curved claws that are not tree dwellers (curved claw-> tree dweller).

I almost picked C because it sounded like that, but C is saying the opposite. C tells us that curved claws are necessary for tree dwellers. If we negate C, saying, there are some tree-dwelling birds without curved claws, then that has no effect on the argument. Okay cool, there are some birds with flat claws who are tree-dwellers, but we do not have to assume this at all in order to believe that if the Archeopteryx had curved claws, it must have been a tree-dweller.

It took an extensive analysis of the stimulus to understand why E is correct and you won't get there till you identify the assumptions and terms in the stim.

• Over the last 25 years, the avg price paid for a new car has steadily increased. This means that that 25 years ago, of ALL NEW CARS SOLD, the average price was say 15k.

• ... in relation to avg individual income. This means that the proportion or the fraction representing new car price / avg income has increased. So 25 years ago, the average price of a new car was 15k and average individual income was 40k. For avg price paid for new cars to increase in relation to income means that proportion is steadily getting higher each year. So 15k/40k (37.5%), then 20k/43k=46.5%. The average price of a new car is taking up more of the average income (so we think).

Remember, we don't attack the truth of the premises. The proportion has increased and we have to accept that. What we can question though, is the assumption behind the proportions- the average price for a new car represents the average price paid by for a new car by an INDIVIDUAL. In order to casually say, "oh yeah, we are just going to infer that if the proportion has steadily increased, that means when my uncle an individual goes to a buy a new car today he will be spending more than an individual spent on average 25 years ago, you would have to assume that individuals are the only ones buying new cars. Why? Imagine a big pizza where each slice represents a category of people buying new cars.

• Some slices represent individual buyers.

• Other slices represent businesses, governments, and rental fleets.

The amount of pepperoni on each slice represents the price paid for a new car.

Now imagine that 25 years ago:

• most slices belonged to individuals,

• and almost every slice had around 3 pepperonis.

So when we average the whole pizza, we get:

• about 3 pepperonis per slice.

Today, however, something changes:

• the business/government slices now have HUGE amounts of pepperoni,

• maybe 15 or 20 pepperonis each,

• while the individual slices still only have 3 or 4.

Now when we average the whole pizza, the average pepperoni per slice shoots way up.

But does that mean the individual slices suddenly have way more pepperoni?

No.

The overall average increased because the non-individual slices became much more pepperoni-heavy and make up a larger share of the pizza. It's the same thing with this argument. If sales to individuals make up a smaller proportion of all new-car sales, then we don't know if its going to be the case that when an individual goes to buy a new car today and average new-car prices and income have increased, that they will be spending more money.

Here are the actual numbers instead of pepperoni. Twenty-five years ago, on average, individuals spent 15K on a new car and they made 40K (37.5%). Today, the average price of a car is 60K (because governments and businesses have driven that price up when they buy really nice fancy cars) , but when individuals go to buy a car, they only spend 20K on average and average income is 60K (33.3%). In this scenario, individuals are spending less in relation to their income than individuals did 25 years ago.

This is dreadfully long, but I hope this helps. This is one of the hardest questions I have taken so far, but it's also brilliant.

When you first read D, it is tempting to be critical of it on the grounds of, "Okay, cool you have more fire pits in caves in the early period than in the period, but what does that tell me about the number of lamps?" You have to understand how the stimulus introduces the function of lamps. Lamps are used for light in caves. It is a perfectly reasonable inference to draw that a greater number of firepits (which provide light) would diminish the need for lamps in caves.

Similar to a strengthen/weaken question, the burden of proof is not that high. We don't need each answer to be an SA that offers total validity to an argument about why there were more lamps in the late period. The key is recognizing that each answer that is capable of contributing an explanation works with the reasoning structure of the argument. That is why E is wrong and A, B, C, and D are capable of some kind of explanation.

A) - lamps count as artifacts and if they are are harder to identify in the early period compared to the later period, that may explain the skewed distribution. There may be just as many, it's just hard to identify them because they resemble a rusted piss bucket.

B)- Similar to AC A. We have found more archaeological sites from the late period than the early period. Turns out the early period cultures were super protective and buried their lamps hundreds of feet below ground.

C)- More efficient can reasonably imply greater production of lamps. Why? Efficiency = ease. This is more related to quantity than variety of lamp.

D)- See above.

E)- Has nothing to do with the reasoning. Imagine more lamps means they take way longer to make because the production process is inefficiently split between eight small workshops. The stimulus has nothing to do with variety so E doesn't explain shit.

@soleluna883 I totally get you. I think because there are so many question types and nuances to each question, it's second-nature to drift away from the argument. That's one of the biggest battles in the LSAT- sticking to what is there between the premise and conclusion.

My thought process the first time I took it was to search for an alternative explanation which is why I actually chose A the first time I saw this question. I thought to myself, well maybe Moore's satisfied customers (the ones who didn't complain) have thousands of raving reviews. That's something that would cast doubt on the conclusion. But, that process is straight up weaken/strengthen strategy and it can screw you over on flaw questions if it comes at the cost of missing the weak support structure. I did have an intuitive sense that the argument didn't consider if there were any other plumbers in town, but I thought that alternative explanation was strong. The intuition that we want to develop, I think, is more about where does the premise not fully support the conclusion. Finding those loopholes or assumptions are where the meat is. The alternative explanation will only make sense after you spot where the support is weak. Hope that helps and let me know what you think.

@soleluna883 The flaw lessons talk about this and from what I see, it generally isn't a good strategy to rely on what does the argument overlook. Arguments overlook a hundred things. This argument overlooks whether Moore's wife started cheating on him and it negatively impacted his ability to be a good plumber for a few months, but overall he's a decent, reliable plumber. It's silly, but the point is, the argument doesn't have to mention every possibility. Our job on this question is to spot the alternative hypothesis/reasoning/evidence that the argument overlooks which make the conclusion unsupported. B is the right answer because it gets at the relationship between the support and the conclusion. The overlooked possibility I mentioned had nothing to do with the support. That's why it makes no difference. B, on the other hand, attacks the jump from "every complaint filed about a plumber's work was filed against Moore" to "there is good evidence that Moore is a poor plumber..."

I think your asking about why B describes the conclusion's shortcoming. If there are few or possibly zero other plumbers around, the evidence we have (100% of complaints are against Moore) doesn't say anything about Moore's work. It just says that he's the only plumber and he's bound to have a few unhappy customers.

I chose B over A and here is why. All the support in p4 for why I thought A might have been right falls under B. The author says, the ultimate difficulty with IR is that it defeats its whole purpose (a theory is supposed to acquire knowledge and it renders that task impossible). The critique of IR not truly being able to know an entity because of the difficulty to know all of its relationships is not based on the principle that entities must be defined in order to have an adequate theory. We are told in p2 and p3 that we can define entities by their relationships with other entities, but those relationships are not always significant enough to change an entity. If you think the author is basing the rejection of IR on the "prerequisite impossible to satisfy", then look to what the points to. It goes back to support the claim that IR defeats its own purpose of acquiring knowledge.

The question stem is asking for a principle that covers the author's argument against IR. All of the points that make AC A attractive are apart of those "consequences" that contradict the basic purpose of IR.

Woah, this turned my brain into mush for a second. AC A is the necessary assumption because it gives us the link that makes the conclusion make sense. If the most beautiful artworks are always the best, then it makes sense to say that beauty does not equal truth. Because the most truthful art is the same as the most realistic art. Sometimes, the most realistic art is not the best, thus sometimes the most truthful art isn't the best. But, if the most beautiful is ALWAYS the best, then it would be impossible to say that beauty = truth because we know of a situation where the most truthful art (the most realistic) is not the best art.

@RajwantKaur I was also swayed by C. It's tempting because you are looking for something in the argument that says following the advertisement's diet may not result in losing weight. I was thinking well, this study is about a group of people already trying to lose weight. How do we do the weight loss was a result of the diet and not a result of other things they might have been doing such as exercise in an effort to lose weight?

I think your question is asking would C be correct if it said that the people who ate more calories from protein rather than carbs and ate their biggest meal of the day for breakfast AND exercised lost MORE weight than those who exercised but didn't follow that same diet. The answer would still be no because the argument is still overlooking the fact that some people in the study may have followed the diet and still lost NO weight or maybe even gained weight. The premise that the conclusion is based on is about a very small subset of people. It's about those who lost the MOST weight. Okay so we know out of this unknown set of people who lost the most weight, they followed the more protein breakfast diet. However, it is still possible that some people followed the diet and didn't lose weight, even if they did exercise. The conclusion is that ANYONE who follows the diet will lose weight and we can't make an anyone claim based on a claim about a select group.

Those who lost the most weight did X is not the same as most people who lost weight did x. Also, most does not imply a more-more correlation. What I mean is based on the argument we can't say yet that the more you follow the diet, the more weight you lose.

I find it very helpful on questions like this to ask yourself what is missing or what link assumptions does the argument make. We know low-watt bulbs cost more and their advantage are enormous. The argument then concludes that everyone should use them. If you think of this as a PSA or SA question, we need a rule that says if something costs more and has massive advantages, then you should use it.