Welcome back! This is the third lesson in our eight-part Insight LSAT prep course. In our last lesson we focused on LSAT logic and arguments. If you haven't seen that one already I definitely recommend checking it out because that's where we laid down the foundation that we'll be building on today. In this lesson, we're really getting down to business.
Instead of discussing general skills, we'll be talking specifically about one of the two main sections of the test, Logical Reasoning, or LR for short. In the LR section, you'll have 35 minutes to answer 24 to 26 questions. Each question will consist of a short passage, usually 1 to 3 sentences, a question stem, which is where you'll find the actual question being asked, and then 5 answer choices, A through E.
The purpose of the LR section is to test your ability to understand and think critically and logically about written information. After all, that's what you'll be doing in law school. Now, an important thing to know early on when it comes to LR is that the questions in this section can be categorized into types.
Here is a list of all the types of questions you'll see on the LSAT Logical Reasoning section. There's structural analysis, sufficient assumption, flaw, strengthener, weakener, necessary assumption, parallel structure, inference, unexpected result, and apply the principle. You may see slightly different lists out there depending on which educational sources you're drawing from.
The types are really there, in the test, so any categorization scheme is going to have to capture these real patterns. That being said, some people choose to group questions in slightly different ways for different reasons. My categorization scheme is a very practical one.
It's based on the strategies you'll need in order to answer questions. When there were choices to be made about how to organize things, I chose to group things together if they require you to use the same skills or strategies. This enables you to stay focused on improvement and not get bogged down in details.
The fact that LR questions can be categorized into types is a really good thing for us because it gives us a straightforward path to improvement. I like to think of this path as involving two main phases. You start off in a controlled environment, where you can learn which types there are, what each type is asking of you, and what the specific strategies are for dealing with questions of each type. You then practice questions by type, sticking with one at a time.
You start with easier questions of that type and gradually move up in difficulty as you get better. Once you reach a certain level of proficiency, you can move on to the next type and do the same thing. Now, the questions on the LSAT will not be labeled by type, so in a second phase you need to head out into the wild and learn to recognize a question's type without it being told to you.
You also need to practice moving flexibly between questions of different types. This is what you'll be doing when you work on LR sections as wholes instead of drilling questions by type. So the basic idea is to have someone explain the question types to you and guide you through your practice before you move on to full LR sections.
If you just jump right out there into the wild, taking full sections before you're ready, logical reasoning may eat you alive. In this video and the next two, we'll focus mostly on the explanation part of things. I'll introduce the question types to you, and I'll give you the strategies.
We'll also do a little practice together on some sample questions. I'll tell you ahead of time, these will be on the easier side of the difficulty scale. Our emphasis right now is just on understanding how these questions work and how to approach them. There will be plenty of time later to challenge yourself with more difficult material. Along those lines, I'll provide homework questions for you after we do our sample ones together so that you can continue to practice on your own.
These ones will feature a range of difficulty. Sometimes people refer to LR as the arguments section. This is a misnomer and it's misleading.
It's true that most questions in the LR section involve arguments, but not all of them do. Inference, unexpected result, and apply the principle questions generally don't have arguments. Among the others, I make a distinction between what I call front-end and back-end questions. questions.
This higher level distinction refers to whether your strategies are mainly executed before or after reading the answer choices. In front-end questions, you read the passage and do considerable work before even reading the answer choices. Sometimes you can even predict the answer.
For back-end questions, this won't be possible, and you'll have to read the answer choices before doing the bulk of the work. The difference between front-end and back-end questions is determined by the nature of the question being asked. This is something that will become a lot clearer to you once we go through the types in more detail.
With that broad distinction on the table, I now want to introduce the general step-by-step approach that we will use for every LR question. Start practicing this from the very beginning in order to set down good habits. The first thing we do is read the question stem.
This may sound a little surprising, but there is good reason for it. We don't want to read the passage until we know why we're reading it. The stem tells us what question type we're dealing with, and this enables us to read with purpose.
Your reading will be a lot more active and focused if you've got your task in mind from the very beginning. Once you read the stem, take a mental note of the question type. This isn't something you'll be able to do at first.
But once you're exposed to more questions, you'll learn how to identify a question type by reading the stem. On the Insight Training Platform, we have an entire module devoted to this skill. The trainer will show you stem after stem and ask you to identify the type.
It's a surefire way of mastering this skill quickly. Next, read the passage. I often suggest that people read the passage twice. Once quickly just to get a rough sense of what's going on, and then again to catch all the detail and follow the argument more closely. But reading styles are personal, so this isn't a hard and fast rule.
Personally, I read in a sort of staggered way. I like to think of it as insisting on understanding. As soon as I feel a little lost, I back up a bit and re-read.
I keep doing this, two steps forward, one step back, three steps forward, one step back, until I get to the end. Now, the next step is to find the conclusion to the argument if there is an argument. Then, again, only if there is an argument, Do a more thorough argument analysis.
You found the conclusion, what reasons are being given in support of it? You can start to see now why it's important to know which question type you're dealing with before reading the passage, and why it's important to know which question types have arguments and which don't. If you're dealing with a question type that doesn't have arguments, you know to skip these previous two steps. But if you're expecting an argument where there isn't going to be one, you'll get confused and waste time.
The next step is to execute the question type's main strategy if you're dealing with a front-end question. If you're not, you move on to the next step, giving a first pass to the answer choices. What do I mean by first pass?
This is an important strategic point that many people don't realize, and I think that's a real shame because it's super powerful. When reading the answer choices, give each of them a quick and easy first pass before getting bogged down in details. Think of it as skimming just to get a sense of what's out there. Remember, just like other language on the LSAT, the answer choices can be quite complex. The mistake I see lots of people make is that they struggle through an answer choice, trying to understand it perfectly, and even to rule it out definitively, before moving on.
They rack their minds over the answer, spending all of this time and brainpower. And then they get to a later answer and recognize it immediately as the right one. All of that work for nothing.
Imagine that you're going to the store, and that you're allowed to buy only one new piece of clothing. Now, imagine that you go about doing this by asking the store clerk to bring you one item at a time in a private room. You examine it carefully and thoroughly, try it on, consider its price, think about how it fits with the rest of your style and wardrobe, and then hand it back to the clerk. You do this over and over until you've fully evaluated each item in the store, and then you make your decision. Or alternatively, imagine that you just casually stroll around the store to get a sense of what's available.
and to see if anything catches your eye. Maybe something jumps out to you and you know that you've just got to have it. You try it on just to be sure, make sure the price is good and that it fits with your wardrobe, and you buy it. Or, if it's not that easy, at least you'll narrow things down to a more manageable set of options, which you can then take a closer look at.
This is how it is with answer choices. With your understanding of the question type and any associated strategies in mind, you want to give the answers a first pass to see if there are any that are obviously right or obviously wrong. And even if things aren't obvious, you can at least get a sense of the relative strength of the choices, so you know how to use your efforts efficiently.
Okay, A and E look like contenders, B and C look pretty bad, and I'm not sure about D. Once you do your first pass, you should read the answer choices again with more detail, but the amount of effort you spend on each answer should be informed by your first pass. This is how you go about things intelligently and efficiently. Typically, Answer choices across the test follow a standard spread of quality. This may be something that's hard to appreciate until a bit later in your preparation, maybe in a couple of months when you've got a lot more experience, but I'll flag it for you now anyway.
Generally speaking, among the five answers you'll have, of course, one that is correct, but then you'll very commonly have one that is second best. Let's call this the challenger. Often it will be quite similar to the correct answer, but have some small detail that makes it worse. On the other side of the spectrum, you'll also have one or two answer choices that are real junkers, answers that are pretty obviously wrong and can be knocked out quickly.
Then the last one or two will be somewhere in the middle. The most important takeaway from this spread is probably the challenger. On your way to becoming a true master of logical reasoning, you can consider it a small victory, or a benchmark, if you can reliably narrow things down to two, where one of them is the correct answer. Even if you pick the wrong one, you reliably get yourself in a position where you've got a 50-50 shot.
Also, there are certain advanced techniques for carefully comparing answers, but you will only realistically have time to employ these if you can narrow things down to a manageable two. It is during your second pass over the answer choices that you'll execute your main strategy if you're dealing with a back-end question. In any case, after you've done your second pass, you choose an answer. Often, it'll be helpful to go back to the passage when trying to make your final choice, but exactly how much of that will be useful is going to depend on the particulars of the question at hand.
You'll get a feel for it and develop your own style over time. Our standard step-by-step approach is just a model. It gives you structure and purpose, but of course, like any other model, It can only take you so far. Make sure to write down this list, and keep it by your side as you progress in your understanding of the LR section.
Eventually, this will become second nature, but it's important in the beginning to explicitly follow these steps in order to lay down good habits. What we've talked about so far in this lesson applies to the LR section as a whole. Now let's move on to our first group of question types, front-end questions.
We'll handle back-end questions in lesson 4, and questions without arguments will be in lesson 5. As I mentioned before, front-end questions are ones where you do considerable work before reading the answer choices. This is because they ask the sort of questions that could actually in principle be fill-in-the-blank questions. Without getting ahead of ourselves too much, let's quickly compare two question types, flaw and weakener.
Flaw is a front-end question type. Question stems will ask you to identify a flaw present in the argument. Notice how this is something you can do even before looking at the answer choices.
The flaw is there, ready to be identified. Weakeners, on the other hand, are back-end questions. Question stems for that type ask you to pick an answer choice that, if true, would weaken the argument. But there are countless things that could weaken any argument, and you can't know which one the LSAT is going to throw at you. You have to read the answer choices first.
When it comes to front-end questions, then, we can often predict the answer, especially as we gain more experience. This is super helpful because in our first pass of the answer choices, we don't need to think, I wonder if this could be a good answer choice. Instead, we can just think, I have an answer in mind.
Is this what I'm looking for? If it's not, you simply put it to the side. No need to judge it as right or wrong for now. Just put it to the side.
If it is the thing that you're looking for, well congratulations! You can confidently hold on to that as you quickly go through the other answer choices. and see if anything else can compete. Then, if nothing else looks promising, just double check your answer choice, and that's it. Move on.
In this lesson on front-end questions, we'll deal with just three question types. We'll start off with structural analysis. Then we'll move on to sufficient assumption, and we'll finish off with flaw.
In order to make things as simple as possible to understand, we'll follow the same format in dealing with each question type, both in this video and in lessons 4 and 5. To begin with, I'll introduce the question type and make some general comments. Then, I'll give you a list of other question types that you should make sure not to confuse this one with. I'll then tell you the frequency with which the question type appears on the LSAT, and I'll also give you some examples of stems that indicate the question type.
Next, we'll move on to discussing the strategies that will be helpful in approaching questions of the type we're working on. Occasionally, I'll take a little detour to describe more general concepts that might be helpful for other question types too, but are especially relevant to the one at hand. I'll also be sure to explicitly mark any specific skills or tools that you should focus on. Once we're done talking about the question type, we'll practice. I'll give you some sample questions, and we'll work through them together.
I'll then finish off by giving you a list of homework questions. The questions for the homework will all come from the same previously administered tests, which you can access on Law Hub or through the Insight training platform. I've reserved tests 101 through 105 for homework, and I've also organized these questions by difficulty.
Easy, medium, and hard. I've created these lists of homework questions specifically for those of you who are engaged in self-guided study for the LSAT. Work through the easy ones first, review your work, and then move up in difficulty. I wouldn't worry about the hard ones in the beginning. Once you finish the medium ones, just move on to the next question type.
Then, come back to the hard ones later. For those of you who are using the Insight Training Platform, you can ignore the homework lists entirely and just use the dedicated training modules right on the platform. For each question type, you'll be given questions that correspond to your skill level, you'll gain experience points for correct answers, and as you level up, the questions will get more difficult.
The platform's algorithm will also tell you when it's time to move on to other question types and when you should go back and try to improve, depending on your personal strengths and weaknesses. The whole system is designed to take all of the organization work off your plate so you can devote yourself entirely to improving your skills. Alright, enough with the preliminaries.
Let's get started with our first question type, Structural Analysis. When teaching people about the LR section, I like to start with structural analysis questions because the skills that you need to use in completing these questions are the most fundamental. and they apply to most other question types as well.
Remember steps 4 and 5 of our standard approach to tackling questions? When a question has an argument, you start by finding the conclusion, and then you do a fuller analysis by figuring out how the other statements in the passage relate to that conclusion. For structural analysis questions, that's pretty much all there is.
Now there are three main ways that the LSAT will test your structural analysis abilities. First, you may be asked simply to find the argument's conclusion. Second, you may be asked about the role that a specific statement plays in the argument as a whole. And third, you may be given a dialogue between two people, where at least one of them is making an argument. And here you'll somehow be tested on your ability to follow that exchange.
All of these tasks test essentially the same skills, finding the conclusion and recognizing relationships of support between claims. The main question type to not confuse structural analysis with is inference. As you'll see in lesson 5, some inference question passages end with a blank, and they ask you which answer choice best fills in that blank.
That's different from the find the conclusion version of the structural analysis question, where the conclusion is there already in the passage, ready for you to find it. Structural analysis questions make up 15-16% of all LR questions, so they're very common. Luckily, they're also one of the easier question types as a whole. Here are some typical stems that indicate you're dealing with a structural analysis question.
Which one of the following most accurately expresses the main conclusion of the argument? The claim blah blah blah plays which one of the following roles in the argument? Name and name disagree over which one of the following, and Name's reply to Name's argument proceeds by...
The first one of these indicates the main conclusion version. The second indicates the role played version. And the last two indicate the dialogue version. As I mentioned already, the main strategy with this question type is to just do a basic argument analysis.
First, you find the conclusion. This is the most important step. And then, try to figure out how the rest of the argument supports that conclusion. Now, for the find the conclusion version of structural analysis, that's all there is to it.
Just pick the answer that expresses the conclusion you've already found. For questions that ask you about the role a certain claim plays, the stem will specify the claim to focus on. Make sure to home in on that when reading the passage. Do your regular structural analysis, finding the conclusion first no matter what, then figure out the rest of the argument.
But now focus on your target claim. Where does it figure into things? Answer that question yourself before moving on to the answer choices, so you don't get tricked by them. The main roles to look out for are main conclusion, intermediate conclusion, support for or against one of the previous two, and opposing view.
Pick the answer that best describes the role you've already identified. When a structural analysis question features a dialogue, at least one of the speakers will be making an argument. The other person will then either also make an argument, usually in opposition, or otherwise somehow comment on the first person's argument, usually by criticizing it.
The stem will tell you what to focus on. But again, the strategy is to find the main conclusion of any arguments being made, and then try to understand how everything else relates. Now let's try applying these strategies to some examples. For each one, I suggest that you pause the video first and work through the question on your own. You'll get a lot more out of it this way.
Then, I'll give you some hints. And this is meant to replicate a nifty little feature that we have on the Insight Training Platform, a feature that I call Insight Mode. While learning, it's good for you to get hints rather than just finding out immediately what the right answer is.
Delaying the big reveal will keep you active and critical. When we enable insight mode in these videos, I'll highlight any signal words that are in the passage, and I'll also highlight the passage's conclusion. I'll also give you hints for each answer choice that encourage you to think about them in different ways.
I won't read these hints out loud, so I suggest that you pause your video again here, read through everything, and think about the question again. After that, we'll disable insight mode, and I'll talk through the question with you. Here's our first structural analysis question.
Pause the video now and work through it on your own. Okay, and enabling insight mode... Now, on our website, insight mode highlights the argument's conclusion as well as any signal words that are there, but I'll hold back on that here for structural analysis questions, since it would give things away.
I'll still give you hints for each answer choice though. So pause your video again now. And think through things again with this new information on the table. Are you happy with your answer? Do you want to change it?
I'll give you a moment to think about it. And we're back. Do you remember our first step from our step-by-step approach? We start with the stem.
The claim that relatively few people donate money to charity plays which one of the following roles in the argument? We can tell that this is a structural analysis question. because it asks about the role that a specific claim plays in the argument.
Here, we are interested in the claim that relatively few people donate money to charity. We'll keep an eye out for that one as we read. Now, on to the passage.
People's behavior is often inconsistent with their professed moral beliefs. Although many claim to believe that it is important to donate money to charity, relatively few actually give. Okay. So there's our target claim at the end, but let's just proceed with our regular analysis. What's the conclusion here?
If you don't see it intuitively, the first thing to notice is that there are three claims in this argument. First, people's behavior is often inconsistent with their professed moral beliefs. Second, many people claim to believe that it is important to donate money to charity. And third, relatively few people actually give to charity. Now, We don't have any signal words, but we can still use the skeptic's perspective or the SO test.
Because we haven't narrowed things down to just two contenders, which is the situation where the SO test is most useful, I'll try the skeptic's perspective. Let's go with the first claim. People's behavior is often inconsistent with their professed moral beliefs.
Why should I believe that? When asking this question, I can see that the next two claims together actually create a sensible answer. They give an example of a moral belief that people have but don't act on, so they serve as support for the first claim about inconsistent behavior.
We've got a positive hit right away. The first sentence is in fact the conclusion. And we can see from this same exercise that our target claim, that relatively few people donate to charity, is one of two pieces of support that work together to bolster the conclusion.
So, the role that it plays is support for the conclusion. Because this is a front-end question, though. We can take the product of our efforts right into the answer choices. Rather than carefully considering each one, we can just see if the answer that we want is there.
And as we scan down, looking for something like support for the conclusion, what do we see? A. It's the argument's conclusion, no. B. It's evidence used to support an intermediate conclusion.
Support is good, but it's not for an intermediate conclusion. There isn't even one of those. C.
It conveys a point of view that opposes the view of the author. That's an opposing view, not what we're looking for. How about D? It is used as evidence in support of the conclusion.
Yeah, that's what we want. And it's almost certainly right. But just for good measure, let's look at E as well.
It is an intermediate conclusion in the argument. No, there are no intermediate conclusions here. So we've got it, D. And that is in fact the correct answer.
And now for another example. Okay, here's another one. Pause the video and work through it yourself. Okay, enabling insight mode.
Now, pause your video again and give it a second thought if you'd like. And we're back! Let's start with the stem. Which one of the following most accurately expresses the main conclusion of the argument?
Another structural analysis question. this time asking us to find the conclusion. Pretty straightforward. Let's read the passage. While it is true that in a recent poll, the majority of students at Birch College said that they purchase organic rather than conventionally grown vegetables, the results of that poll should not be taken to reflect the practices of the student population more broadly, since it was based on an unrepresentative sample.
Birch College is one of the most expensive schools in the nation, and its students mainly come from wealthy families who can easily afford organic foods. For students who are on a more typical budget, however, These premium groceries are out of reach. Here we have a signal word, since.
The way it is positioned in the sentence, it looks like the claim afterward is being given as support for the claim before it. And yes, that seems to check out. If a poll is based on an unrepresentative sample, that's certainly a reason to think that the poll's results won't reflect the views of a broader population. But what about the rest of the passage? We still have to account for that.
Let's look at the next sentence. Birch College is one of the most expensive schools in the nation, and its students mainly come from wealthy families who can easily afford organic foods. Okay, two claims.
One about the cost of the school, and then a second about the students'families. Those ideas seem to be unpacking the notion that the sample is unrepresentative. Not everyone is wealthy, after all. And then that last sentence really drives it home, saying that for students who are on a more typical budget, organic food is out of reach. It looks like the rest of the passage is thus support for the idea that the sample is unrepresentative, which seems to be an intermediate conclusion on the way to the final conclusion.
Okay, so our signal word gave us an initial clue as to where the conclusion was, and we checked the rest of the passage to verify. I think we've got it. The conclusion is that the results of the poll shouldn't be taken to reflect the practices of the student population more broadly.
Do we have that in our answer choices? Yep, there it is in answer choice C. Take a look at the other ones for good measure if you'd like, but C is going to be our correct answer. Notice how it doesn't make as much sense to say for front-end questions, well, why isn't D correct?
Or, what's wrong with A? Because we've done work up front, we already have something in mind, so we're not trying to defeat the answer choices. We're just trying to find the answer that we've already selected.
Let's do one more. Okay, you know the drill by now. Pause your video and try it on your own. And insight mode enabled... now.
And we're back. Let's begin with the stem. The dialogue provides the most support for the claim that Maggie and Darlene disagree over which one of the following.
Okay, one of the dialogue-based structural analysis questions. Have no fear, we can handle this. Let's read the passage. We start with Maggie.
Unlike in the past, today's technologies allow people to carry on long-lasting relationships with others over the internet without ever meeting them in person. This is unfortunate. Without a strong foundation in shared experiences, a relationship between two people can never be more than a casual acquaintance.
Okay, we can already see that Maggie's got an argument. She combines the first idea about what today's technologies facilitate with the last idea that these relationships aren't based in shared experiences and thus can never be more than casual acquaintances, and she concludes from all of this that the current state of things is unfortunate. If you thought that maybe the last sentence was the conclusion, try running the SO test. Okay, let's move on though.
So Maggie says all that stuff. Now, Darlene's response. Even if the- types of experience differ from those of earlier generations.
It is still possible to have shared experiences online. Nowadays, people meet via video conference to discuss mutual interests, and some activities like book clubs can even occur without in-person contact. Also, modern video games are often multiplayer, allowing players to compete or cooperate in virtual worlds. Alright, so Darlene has an argument as well. The conclusion is that it's possible to have shared experiences online, and we can see that because the rest of our statements revolve around it.
The first part is just giving a little qualification, and the parts after are examples of shared experiences online. Okay, so when you're dealing with a disagreement question like this, you have to locate something that both speakers have somehow addressed. It may not be explicit for one of them, it may be implied, but they both have to address it somehow. Now, Darlene only really picks up on part of what Maggie is saying.
She doesn't just go along with the story and then disagree at the end, saying that actually it's a good thing that people can only form casual acquaintances. We can tell that she disagrees with Maggie, but how precisely does she do that? The key seems to be about the shared experiences. That's what her whole argument is about, after all. Does Maggie mention those?
Yes. She's assuming that people can't have shared experiences online, which is why she says, without a strong foundation in shared experiences. Obviously, she's talking about relationships that are held over today's technologies when she says that. So Darlene thinks that people can have shared experiences online, while Maggie does not.
That's what they disagree over. Is it in the answer choices? Yep, answer choice B.
On the test, I'd just choose that one and move on. But to drive home this point about both people mentioning it, I'll talk through the other ones as well. For A, Maggie certainly thinks this, but Darlene doesn't say anything about what deep personal relationships require. She's just talking about having experiences together.
For C, Maggie seems to think this, but Darlene doesn't comment on it. For all we know, she could agree with Maggie. Her point is just that you can have shared experiences online.
But maybe she thinks that the relationships you form there will never be as valuable as in-person ones. Or maybe she doesn't. We just don't know her views on that topic. For D, again, Darlene doesn't really comment on relationships. I guess if we make the jump from meeting to discuss mutual interests or cooperating and competing over games, and we call that relationships, I guess we could entertain this answer a little bit more.
The problem is that Maggie and Darlene would probably agree about this answer choice anyway, so that's not good. And E, that one's a real junker. Maggie mentions long-lasting relationships, but Darlene doesn't say anything about how long a relationship will last.
B is the best answer by far. Okay, I hope you did well with those. Here is your homework for structural analysis.
Remember, this is just for those of you engaged in self-guided study. For those of you on the Insight training platform, just do the drills on the website. You can pause the video now to take a screenshot of this, or you can find the same list at insightlsat.com slash homework.
In general, I would recommend going through the whole course before doing any homework. That way, you expose yourself to all the material and begin making connections. Then you can go back, rewatch just the segment on the question type you're about to focus on, and then do the easy and medium homework questions.
Then, later in your prep, you can come back to the hard ones. This spaces out your engagement with the material and facilitates more long-lasting learning. Alright, pause the video if you're going to, because we are moving on now.
Sufficient assumption is a question type that takes some time to warm up to. The reason is that it involves concepts that may be unfamiliar to many test takers at first. I think the best way to ease into it is to remind you of some ideas that we discussed in lesson 2. If you remember, in that lesson, I said that sometimes arguments can feel like just stacking up reasons on one side or another of an issue, but that other times, especially when conditional logic is in play, the arguments can feel a lot tighter.
Let's revisit that idea now. Remember the pizza argument? The best version of it we came up with went like this. We had two pieces of support, Pizza is delicious, and pizza is affordable, and we concluded that we should order pizza for dinner tonight.
Now, this is definitely an argument in the sense that reasons are given in support of a conclusion. But it's not a particularly strong one, to be honest. Imagine if I were an opponent, and I just said, Pizza is unhealthy, and I had pizza yesterday, therefore we should not order pizza for dinner tonight.
These seem like perfectly good points in response. And now we've found ourselves playing the game of comparing the strength of various reasons. But imagine instead that we were able to add a third piece of support to our original argument.
Pizza is delicious, and pizza is affordable, and if a food is both delicious and affordable, you should definitely order it for dinner. Therefore, we should order pizza for dinner tonight. Now, to be perfectly frank, this is a stupid argument. The third piece of support that I gave expresses an obviously problematic and false statement.
Nobody actually believes that a food being delicious and affordable is enough to make it the case that you should definitely order it for dinner tonight. Plus, if that were true, you'd actually have to order every food that is both delicious and affordable, and that would be chaos. So this is a sense in which this argument is really, really bad.
However, I want you to put aside those sorts of judgments for now and think structurally instead. Even though that third piece of support is obviously false, what if it were somehow true? What would you think of the argument then? It would actually be extremely strong. Just like the arguments from lesson 2 that also used conditional logic, the conclusion here just falls out of the support as a matter of simple inference.
It's now just like the Socrates argument. Socrates is a man. All men are mortal.
Therefore, Socrates is mortal. Our new bolstered pizza argument is so much stronger than it was before. In fact, notice that it is impervious to the other considerations we raised a moment ago.
The fact that pizza is unhealthy or the fact that you had it yesterday don't affect this argument at all. They are suddenly irrelevant because we have a rule about what we're supposed to do when food is delicious and affordable, and it doesn't make any exceptions for health or redundancy. What we've done here is tightened up this argument.
We removed the gaps between the support and conclusion, the same gaps that other competing ideas were slipping in between before. Again, Put aside the fact that we did this tightening with a dubious claim. The point is a structural one. If we were somehow able to take this third piece of support on board, the argument would be in great shape. Sufficient assumption questions ask you to select an answer choice that, if you were able to take it on board, would tighten up the argument.
You don't question the plausibility of answer choices for this question type. You grant their plausibility, and instead focus on logical structure. It's called sufficient assumption because the answer choices are assumptions that you're being allowed to make.
Which one of them is sufficient or good enough to fill the gaps in the argument? Now, there are two other question types that I don't want you to confuse sufficient assumption with. The first is necessary assumption, which we will get to in the next lesson.
Those sound similar but are very different. Correct answers there provide assumptions that are needed for the argument to work. If you can't bring them on board, the argument will fail.
In contrast, you don't need the correct answer choice for sufficient assumptions. It's just good enough. The big difference is that something may be good enough by being too good, in which case it would be sufficient but not necessary. For example, imagine that you wanted to buy a cookie at the store, and the clerk said it costs $1. $2.
This would mean that it is necessary to pay $2 for the cookie. It's also sufficient, it'll get you the cookie, but let's focus on the necessity for now. You need to pay $2 for the cookie.
But what if you then replied, all right, but how about I give you $100 for it? I'm sure the clerk would be delighted. $100 is certainly good enough to get the cookie, but it was never required.
So it's sufficient, good enough, but not necessary. We'll revisit these ideas when we talk about necessary assumption questions in the next lesson. For our purposes now, the upshot is that answers for sufficient assumption questions can be way stronger than they need to be.
That's not a problem here. The second question type you shouldn't confuse sufficient assumption with is strengthener, which we also discuss in the next lesson. Strengtheners ask you to find answer choices that, if granted, make the argument stronger.
But they aren't about structure or tightness, usually. They're more like adding another independent reason in support of the argument. So if we have our original pizza argument, pizza is delicious and pizza is affordable, therefore we should order pizza for dinner tonight, a correct strength in our answer choice might add something like, every pizza comes with a brand new car for free.
Add that to the argument and it really seems like the question is settled. But notice that it's settled in a very different way than with the sufficient assumption questions. The reasons stacked up are really powerful.
but they aren't logically tied together in the same way. If this difference isn't clear to you yet, I recommend spending an extra moment considering these ideas and perhaps going back a few minutes in the video to rewatch. Sufficient assumption questions are relatively rare, making up only 5-6% of all LR questions.
So, while I strongly recommend that you prepare fully for the test and learn all of the question types to the best of your ability, you can make sufficient assumption a lower priority, especially given that it involves a somewhat trickier concept. Stems that indicate sufficient assumption questions make reference somehow to the idea that the argument will be made right or fuller if you are allowed to take the correct answer choice on board. Here are some examples. The main conclusion above follows logically if which one of the following is assumed. The conclusion can be properly inferred if which one of the following is assumed.
Which one of the following, if assumed, enables the conclusion of the argument to be properly drawn. These ideas of following logically, being properly inferred, and being properly drawn are all talking about the logical structure of the argument. In the LSAT sense of the words, a conclusion follows logically, or is inferred or drawn, when we're dealing with the tighter arguments. The pizza argument, before we bolstered it, may have had some reasons in support of a conclusion, but that conclusion wasn't inferred, strictly speaking.
It didn't follow or fall right out of the reasons in the way that the conclusion does when things are logically tighter. To help you deal with sufficient assumption questions, I'm going to introduce a new skill and a new tool here. The skill will be finding the gap in the reasoning. The tool will be the bridge, since you'll use it to fill the gap once you've found it.
Let's talk first about finding the gap. In sufficient assumption questions, there will usually be a jump that is made somewhere in the argument. Usually, this is a jump from one idea to another intuitively related but technically distinct one. So imagine if someone said the following to you.
There is never any crime in our neighborhood. It is an extremely safe place to live. Now, this sounds fine, but crime and safety are two different ideas. We can tell this because they can come apart.
Some places have no crime at all, but are still not safe. Think about what it would be like to live on the edge of an active volcano. So there's a gap in this reasoning between the idea of crime and the idea of safety.
Here's another simple example. Moneybags Academy has the highest paid teachers of any in the district, so the students at Moneybags are receiving the best education in the area. You have to make the leap from having the highest paid teachers to offering the best education in order to go along with things here. Maybe it's a plausible leap to make, maybe it's not, I don't know. My point is just that they are conceptually different things.
There's a gap. We want to keep an eye out for gaps in reasoning when it comes to sufficient assumption questions. That's our main front-end strategy.
Once we find the gaps, we can use the bridge to fill them. The correct answer in a sufficient assumption will bridge the gap by making a connection between the concept on the one side and the concept on the other. So in the first one, if we had an answer choice that said any neighborhood that never has any crime qualifies as extremely safe, and we could take that on board for our argument, we would bridge the gap.
For the second, if we had an answer choice that said, having the highest paid teachers guarantees that students receive the best education, then we would again bridge the gap. Notice that the bridge has to touch both sides of the gap, meaning that it has to make reference to the concepts on both sides. That's how it links them and serves as a bridge.
This will become easier with practice. Let's try a couple of examples together. Here's the first one.
Pause your video and give it a try. Okay, and now that we're done with structural analysis questions, I'll enable the full insight mode with the conclusions in the signal words. I'll do that now.
Notice that the word since is not a signal word here. It's about time rather than support. I'll give you a moment now to think things over again.
And we're back. Let's start with the step. The argument's conclusion follows logically if which one of the following is assumed.
Okay, a sufficient assumption question because it says that the conclusion will follow logically if we take one of the answer choices on board. Now, the passage. Despite what he says, the new congressman is not concerned with the views of his constituents. Since being elected 11 months ago, he has not held a single town hall meeting. This is a pretty simple passage.
The first little bit doesn't really seem to matter all that much. But then we have the idea that the congressman isn't concerned with the views of his constituents. And we can see that that is the conclusion, because the next sentence is offered as a reason to believe it. Why should we believe that the congressman isn't concerned? Because he hasn't held any town hall meetings.
Great. So where's the gap? Here, it's between the idea of concern and the idea of holding town hall meetings. It sure seems like a representative concerned with the views of their constituents, would hold town hall meetings.
But those aren't the same thing, and presumably they could come apart. Maybe there are other ways to gauge the support of your constituents. Or maybe the congressman has some legitimate reason for not holding the town hall meetings, but he's upset about this fact and he's still concerned.
This gap between concern and the meetings needs to be bridged. By realizing this up front, we do our front-end work and prepare ourselves to tackle the answer choices intelligently and efficiently. In my first pass, I'm going to mostly ignore any answer choice that doesn't at least refer to both concepts that need bridging.
Okay, I see concern and meetings in A. We'll just hold on to that one for now. In B, there's no mention of concerns, so that's not looking good.
C has both ideas in it, good. D doesn't say anything about concern. And E doesn't say anything about concern.
So really, I just need to consider A and C more carefully. A says that other people who were concerned held town hall meetings. If we take this on board, it would strengthen the argument.
I suppose, since it shows that there has been a pattern of showing your concern by holding town hall meetings. But this answer choice is about other people, so that's not really going to tighten things up here since we need something that refers to this person. C, on the other hand, says any representative who fails to hold at least one town hall meeting is not concerned with the views of their constituents.
Well, that's really powerful. The congressman in our passage counts as a representative who fails to hold at least one town hall meeting. And this answer choice, if we can take it on board, therefore allows us to conclude that he's not concerned. So this is a great bridge, and indeed it's the correct answer.
Now before we move on, notice that the answer choice is technically too strong. It's more than we need, since it refers to any representative, while our passage only refers to a congressperson, which is only one type of representative. And our passage actually only refers to one particular congressman.
So C gives us a big sweeping claim that's much more than we really need. Nonetheless, a bridge that is too strong is still strong enough. It's fine to go overboard with sufficient assumption answers. Let's do another one. Here you go.
Pause the video and try it yourself. And the full insight mode enabled now. And we're back. We start with the stem. Which one of the following, if assumed, enables the argument's conclusion to be properly drawn?
Very similar to last time. To be properly drawn is a matter of logical inference. Which one of the following will allow that, if assumed? Clearly a sufficient assumption question.
On to the passage. A business venture can only be successful if its founding partners are able to resolve disagreements among themselves. And people are able to resolve disagreements among themselves only if they are honest with each other. Throughout the process of opening their new cafe, then, it is clear that Morrison and Jericho have been honest with each other.
Okay, we've got a signal word here, then. It's one we haven't seen yet in this course, and it's a bit of a more subtle one, but it indicates a conclusion. Indeed, this last claim that Morrison and Jericho have been honest with each other, does seem to be where things are all heading. But now, hopefully in reading this one, your conditional logic alarm started going off.
Notice that the first two sentences have the word only. This passage is one of the examples I referred to last lesson, where it's full of conditional logic. I'm excited to do this one with you, because it gives us a chance to appreciate the power of the if-then, a tool I hope you remember from last time. As I think you're about to see, This question is really annoying if you don't use the if-then, but it's really easy if you do. Let's jump right into it, translating our conditional statements into if-then format and then building our little machines.
First one, a business venture can only be successful if its founding partners are able to resolve disagreements among themselves. All right, so if founding partners are not able to resolve disagreements among themselves, then their business venture cannot be successful. If not R, then not S.
And immediately we get our second if-then for free by taking the contrapositive. If S, then R. If you're not sure why or how I did that, go back and review lesson two.
But anyway, this says if a business venture is successful, then the founding partners must be able to resolve disagreements among themselves. Next one. People are able to resolve disagreements among themselves only if they are honest with each other. Okay.
So if people are not honest with each other, then they will not be able to resolve disagreements. If not H, then not R. And the contrapositive, if R, then H. If people can resolve disagreements, then it must be that they're being honest with each other.
Now here's the trickier part. The conclusion is just H. Jericho and Morrison have been honest with each other.
Now, let's take a look at everything we've got laid out. Notice first that we can chain together some of our if-thens. ifs then r and ifr then h can be linked together like this. ifs then r then H. If a business venture is successful, then it means the founding partners were able to resolve disagreements, and that in turn means that they were honest with each other.
We can also link together if not H, then not R, then not S. Applied to this situation, it's that if founding partners are not honest with each other, then they will not be able to resolve disagreements, and then in turn their business venture will not be successful. Now, The conclusion of the argument is H. That's where we want to get.
So it's the first chain here that really seems the most important for us. Remember, when it comes to if-then machines, if we have our input, then we get our output. And the argument wants that output.
It's asserting the output, but we know from the fact that this is a sufficient assumption question that something is missing. Hopefully you can see it by this point. We don't have our input. Nowhere in the argument does it say that Jericho and Morrison were successful. If it did say that, if we were able to take that idea on board, then we could ride our if-then chain all the way to the conclusion.
They were successful, so they must have been able to resolve disagreements. That's an output right there. But then it also becomes an input, and we keep rolling.
They were able to resolve disagreements, so they must have been honest with each other. And that's the argument's conclusion. Okay, a fair bit of work up front. And this is definitely something that will take significant practice to get good at.
But once you can get this far, you're in really good shape. Scanning down through the answer choices, we can see what we want right there in D. Morrison and Jericho's new café has in fact been successful.
What's great about doing it this way is I don't have to puzzle through confusing answer choices like A, B, and E. They are all if-then statements, and I have to figure out what would happen to the argument if I took them on board. That's a lot to think about. But I already know that all I need is the actual fact that Morrison and Jericho have been successful, and then I can use the rest of the argument's claims to get to its conclusion.
So we just skip all that struggle. If this went by a little too quickly for you, definitely rewind a bit and follow my reasoning again. If you didn't do it the same way when you were working on the problem yourself, rewind back to the beginning of the question and try it out for yourself using the if-then method. After all, practice makes perfect. The last thing to say about this one is that there was, in fact, a gap, just like before.
The gap was between one of our if-then chains, if s, then r, then h, and the desired output, h. You can't get from a conditional to its output unless you know that you're in the right condition. That itself is a sort of gap. Sufficient assumptions can be tricky at first, but stick with it. Here's a list of homework questions for you to practice on.
Again, you can also find this on insightlsat.com slash homework. Take note of these because we are moving on. Our next and final question type for this lesson is flaw.
These ones really test your ability to evaluate arguments. So it's definitely a question type where you need to start with a strong argument analysis. Make sure you understand things and then you can take up a more critical perspective. Flaw questions can be quite challenging at first, but they're also among the most learnable of the question types.
The reason is that there's really only a limited number of standard flaws that the LSAT wants to test you on, and you can learn these. I actually recommend that over the course of your preparation, you keep a little list of the flaws that you find. You'll start to notice patterns.
The questions may have different content, be about different subject material, but the flaws are the same over and over again. They're just wearing different clothing. The question type that people most often confuse flaw questions with is weakener.
They're pretty different though. Flaw questions describe problems in the argument. Most of the time this is done in abstract, general language, talking about the argument itself.
Weakeners, on the other hand, provide considerations or possibilities that, if true, would challenge the argument. They might talk about some other situation, and you're asked to think about what effect there would be on the argument if that situation were actually going on. This is different from describing a problem in the argument as it stands.
Flaws show up between 15 and 16% of the time, making them among the most common question types. Time spent learning the different flaws and practicing this question type is well worth it, highly likely to translate into points. As I mentioned a moment ago, answer choices and flaw questions describe a problem in the reasoning. Sometimes this is done using general, abstract language, and sometimes it is done with direct reference to the content of the passage.
In either case, the stem will either explicitly use the word flaw or say something similar. Here are some examples. The argument is flawed because it... Which one of the following most accurately describes a flaw in the argument above?
The reasoning above is most vulnerable to criticism on the grounds that it... That last one is a little harder to catch, but it's basically saying that there's a problem with the argument, so you could criticize it by pointing that out. Now, on to strategy.
Our strategy for flaw is going to be a pure example of front-end work. Once you realize you're dealing with a flaw question, you'll do a good argument analysis. But then, you'll find the flaw on your own without looking to the answer choices. What's the problem here? Crucially, I want you to try to say it to yourself, and to do this as precisely as possible.
Over time, you can get better and better at knowing some of the major options, and you can look out for them. But still, from the very beginning, try to put the problem you're sensing into words. Even jot down a note, if you'd like.
There's definitely something there. You know that from the question stem. Can you find it? And can you put it into words?
If you can, then all you have to do is see which answer choice matches. If you can't, or you can't do it precisely enough, you're going to have to look to the answer choices for some help. Then you can ask yourself, okay, is that going on here?
But then you're in riskier territory, because the answer choices are designed to trick you. To the extent possible, and hopefully increasingly over time, we want to treat this question in a front-end manner and try to predict our answer. Let's try it out with some examples.
Here's our first sample flaw question. Pause your video and give it a try. And insight mode enabled now. And we're back.
Let's check out the stem. The argument is most vulnerable to criticism on the grounds that it... This stem treats the answer choices like fill in the blank. likes, but notice that it wants us to describe a flaw that could be used in a sharp criticism of the argument. Let's check out the passage now, knowing we are looking for a flaw.
Most physicists are good at performing calculations in their heads. Therefore, people who have this ability must be attracted to the study of physics. Okay, short passage with a nice clear signal word.
The second claim is the conclusion. The first is the evidence given in support. What do you think of this argument? People who are already physicists are good at mental calculation.
Does that mean that they came to the profession with that ability? No, it doesn't. We can reach this endpoint, being a good physicist who is good at something, from at least two different pathways.
Either we could have the mental calculation skills already and be attracted to physics, or we could gain the mental calculation skills through the study of physics. As an analogy, imagine if it said Most physicists are good at physics. Therefore, people who are good at physics must be attracted to the study of physics. Obviously you get good at physics by studying it. Maybe something similar is true of performing calculations in your head.
What we have here is a version of a correlation and causation flaw. When two things are observed together, we can never be sure if that's because of a causal relationship between them or not. Take smoke and fire for example.
You always see smoke. where you see fire. But that's because fire causes smoke. Now, for another example, take the fact that in summer, sales of sunscreen and sales of sunglasses both go up.
Obviously, neither of these increases is causing the other, even if both always occur at the same time. It's just the summer weather and people's responses to it that are responsible for both. There's a correlation, but there's not causation between them. Here we have physicists being good at mental calculation.
The argument makes the mistake of thinking that the causal relationship goes from being good at mental calculation to being a physicist. But it could just as easily be the other way around. Or it could be a coincidence, a mere correlation. Mistakes of this sort are very commonly featured on the LSAT.
Let's see if we can find an answer choice that addresses this crucial issue. Scanning down... A doesn't... B doesn't. C doesn't.
D does. It uses the phrase as a result of. which is causal language, so that's looking promising.
And just for thoroughness, since I'm almost there, E, no mention of causation or correlation. Now, we just double check that D actually gives us what we need. Okay, the argument is most vulnerable to criticism, on the grounds that it fails to consider that a person may become better at mental calculation as a result of studying physics. Yep, it definitely does that, because the evidence in the passage equally supports the conclusion in the passage and the conclusion given in answer choice D.
And if it turns out that what's really going on is that people get better at mental calculation as a result of studying physics, then the conclusion in the passage wouldn't hold. Let's try another one. Okay, you know the drill. Pause and try it yourself.
And insight mode enabled now. And we're back, right to the stem. Which of the following points out a flaw committed in the argument? Clearly, this stem is asking us to find a flaw. Let's read the passage and do it.
In the past few years, a particular glacier in Antarctica has increased in mass by nearly 6%. This occurrence clearly demonstrates that the scientists who believe in global warming are wrong. Okay, another short one, and I think the argument analysis is pretty clear.
The glacier has increased in mass, and this is being used as support for the conclusion that the scientists who believe in global warming are wrong. If you're having trouble seeing that intuitively, I think the SO test will do the trick here. So what do you think of this one?
It talks about a particular glacier, one glacier, and it has become a little bigger. And this is supposed to defeat the idea of global warming? Hopefully you can see that that's a real stretch. So since it seems obvious enough, let's practice something a little more challenging.
Can you put this problem into words? Pause the video if you want to give this a try on your own. I'll give you a moment.
Okay. I might say something like, this argument concludes more than it deserves to, or that the evidence isn't good enough to justify the conclusion. Let's see if that does the trick.
A. The argument draws upon irrelevant evidence. I mean, that's sort of in the right direction, but it's not irrelevant.
The size of glaciers certainly would seem relevant to the question of whether the Earth is warming. My problem was about the strength of the evidence, so I don't really like this one. B? No. It doesn't attack the scientists, it just says they are wrong, and it gives a reason, weak as that may be.
C? Cause and effect. No, unlike last time, that doesn't seem to be implicated here.
The argument draws a conclusion that is too general given the evidence provided. Yeah, that could work. The passage claims something about the whole planet from the evidence of one particular glacier, after all. I like this one. And E. The argument draws support from evidence that presupposes the conclusion...
No, the evidence is the mass of the glacier. That doesn't presuppose anything, really. D is the only real contender.
and it matches what we were looking for, and in fact, D is the correct answer. Notice that this second sample question featured a different type of flaw from the one featured in the first sample question. Why don't we do one more together now? Pause the video and work through this one. Good luck!
And some hints from insight mode coming now! And we're back! Let's check the stem. The reasoning in the letter writer's argument is most vulnerable to criticism on the grounds that This stem is very similar to our first example.
We're being asked to find a flaw that can be used to criticize the argument. Let's read the passage. This one is a letter to the editor, and here's what it says. Your paper recently published an opinion piece by a town resident who argued that the school budget should be cut in order to bring down municipal taxes and make it more affordable to live here. The views expressed in that article should not be taken seriously, however, because the author does not have any school-aged children and so is obviously motivated by self-interest.
Okay, let's begin with the argument analysis. We've got a few distinct claims here, and this whole thing is being said by a letter writer. First, we note that there was an opinion piece.
Then we have what that piece argued, that the school budget should be cut. Then we seem to get the author's point of view, that the views in that article should not be taken seriously. And hopefully you can already hear that that's something we'll need support for. Why should I believe that, letter writer? Well, it's because the author does not have any school-aged children, and so is obviously motivated by self-interest.
Okay, so the first sentence is pretty much background information, and the second one gives a short argument. We shouldn't take the article seriously because of two features of its author. And technically those two features form a mini-argument of their own. It seems that the fact that the author doesn't have any school-aged children is given a support for the idea that the author is motivated by self-interest.
So the idea that the author is motivated by self-interest actually seems to be an intermediate conclusion here. We'll see if that matters. Ultimately this is an argument for the conclusion that the claims in the article shouldn't be taken seriously.
So what's wrong with all of this? Remember, on the LSAT and in law, arguments are not fights. They involve giving reasons in order to convince your listeners or readers of your conclusion. Importantly, they're not personal.
The best reasons are impersonal, meaning they can be appreciated by anyone. That's how you convince someone, after all. This argument is getting personal. The issue at hand is whether or not to cut the school budget, and the previously published opinion piece gives some reasons for why we should do that.
This will bring down taxes and make it more affordable to live in the town. Now remember, we're not here to really judge those reasons right now. We just have to recognize that they are reasons. They count in favor of cutting the budget, whether or not that's the best thing to do overall. Now, when our letter writer responds, notice that they don't give the right kind of reasons.
They attack the author directly using personal information. The problem here isn't just that that's mean. It's actually that it's a really weak way of arguing.
If you go about things this way, and you discredit a particular speaker, the problem is that you still leave the real issue unaddressed. So now, what if someone else just pops in, someone who does have school-aged children, and gives the exact same reasons? We should cut the budget to lower taxes and make it more affordable to live here. Now your argument doesn't apply at all to this person, so you're left with nothing.
This is a huge problem. And it's one that you will see from time to time on the LSAT. You can't attack the person speaking.
You have to focus on the substance of the issues. Let's quickly check our answer choices for something along those lines. Scanning...
Scanning... E. It attacks the person making an argument rather than addressing the reasons given in favor of that argument's conclusion. That's what we want, and it's our correct answer. Now, on the test, I would just pick that and move on.
But for the purposes of this video, I'll give you a few comments on the other answer choices. Let's start with A. A says something that we don't actually require of arguments.
You can attack an argument without additionally providing positive reasons for the opposite conclusion. That's fine and valuable, as long as you stay focused on the substance. So this one doesn't work. On to B.
This one is really not a compelling answer. Perhaps the clearest reason is that it's not a good argument. is that it would be the opinion article writer who was doing this, if they're doing it at all, not our letter writer, and that's the target of our criticism.
On to C, what's so vague about self-interest? Sometimes vagueness is a problem on Flaw Questions, but it's only when there are two reasonable interpretations that would have different effects on the conclusions drawn, and I don't really see that here with self-interest. And lastly, D.
Maybe this one comes kind of close. Maybe we could consider this one the challenger. It's obviously worse than E, which gets at our issue directly. And, to be more precise, even if we grant this, the idea of valuing public education is pretty weak.
The opinion article writer may value public education to some degree, but still be acting from self-interest in wanting to slash the budget. So even if our argument is failing to consider this, it doesn't really matter much. So E here. E is definitely our best answer. Okay, and here's your homework for Flaw.
Like I mentioned, this is among the most learnable question types. I recommend that you make a list of the flaws as you encounter them on the test, right from the very beginning. Soon, you'll find that you're not adding new items to the list, but noticing instead that you've already got them written down.
In fact, I can start your list off right now. Take a last glance at this homework list. because I'm about to move on and give you some common flaws.
And I'm doing that right now. Here's a list of common flaws to get you started. We can start with the three that we just saw. Correlation and causation. Insufficient evidence and ad hominem, which is the Latin for attack on the person.
And now I'll add a few more for you. Shifting terms. This is when the argument provides support for one thing, but then makes a conclusion about something else.
You could think of it as a form of insufficient evidence if you wanted, though this one's really more about relevance than strength usually. Unrepresentative sample. This is one you'll get when dealing with research studies or experiments. The study is done on a group that has unusual traits relative to the broader population that the argument makes a conclusion about. We actually saw something like this with Birch College and the organic vegetables, even though that wasn't a flaw question.
Part and whole confusion. Just because a part of something has a property does not mean that the whole does. For a simple example, consider a soccer team. A soccer team is made up of players.
It's a whole that has parts. Now, Those parts, the players, have families, but the soccer team as a whole doesn't have a family. In the other direction, a soccer team as a whole has an owner, but the individual players, the parts, don't have an owner. And finally, necessary versus sufficient conditions.
We've touched lightly on this topic a few times now in the course, and I encourage you to keep an eye on it and develop your understanding of it over time. Basically, you can't confuse some things being good enough for it being required. Wheels are required for driving, but they're not good enough.
$100 is good enough to buy a cookie, but it's not required. And there you have it. That's a strong start to your list. I encourage you to add to it yourself in the coming months. You'll find that flaw questions get easier and easier this way.
Alright, let's wrap up now with a summary and a preview of our next steps. In today's lesson, we began by discussing the logical reasoning section in general. It's a section designed to test your ability to understand and think critically and logically about short passages of written information.
There are 10 types of questions asked in this section, and we can divide them broadly into front-end questions, back-end questions, and questions without arguments. However, in dealing with questions of all these types, we're going to be following a pretty standard step-by-step procedure, where there are just a few alterations depending on the type that you're dealing with. If you haven't already, you should write this step-by-step.
process down and keep it by your side. Step 1. Read the stem. Step 2. Take a mental note of the question type.
Step 3. Read the passage with your task in mind. Step 4. Find the conclusion, if applicable. Step 5. Do a more thorough argument analysis, if applicable. Step 6. Execute any front end strategies that apply. Step 7. Give the answer choices a first pass.
Step 8. Give the answers a second pass. Step 9, execute any back-end strategies if applicable. Step 10, choose your answer.
In the remainder of the lesson, we went through the three front-end question types. Structural analysis, sufficient assumption, and flaw. I gave you an overview of each type, mentioned some types you don't want to confuse it with, gave you the frequency, and some sample stems, and discussed strategies.
We then did some samples, and I gave homework for those of you on the self-guided track. Next time we'll proceed in much the same way, though instead of front-end questions we'll work on back-end questions. There are four of those, strengthener, weakener, necessary assumption, and parallel structure.
When you're ready, meet me in lesson four where we'll go over those. I'll see you there.