LSAT Whole Vs Part Flaw Tips in 4 Minutes

In this video, we'll cover all the flaws that you will find on the logical reasoning section of the LSAT. If you watch this video from start to finish and understand each flaw, then you should never get an R-flaw question incorrect. You'll become an absolute master and lay waste to all these flaw questions. Total domination. So without further ado, let's look at our first flaw. Contradiction. Contradictions are a relatively simple flaw. Basically, they state one idea, fact, or position, and directly contradict what was previously mentioned. For example, if I initially stated all dogs are good, but later state my dog Baxter is bad, then I'm not being logically coherent. My statements cannot both be true. Either all dogs are not good, or Baxter is in fact a good dog. In this case, Baxter is actually a wonderful dog. Confusing the sufficient condition with the necessary condition flaw. That might be a mouthful and confusing at first, but no worries, we'll break it down for you. This is one of the most famous flaws in the LSAT, and it's pretty easy once you know how to break it down. Basically, if you see a conditional, also known as an if-then statement, and they reverse it, then that is a fallacy. For example, if you have A to B, and they later state B to A, that does not logically follow. It should also be noted that the contrapositive of that also does not work, which would be A to B, and not A to not B. To see why this does not work, we can look at a real world example. If you live in Florida, then you live in the USA. You cannot arbitrarily flip it as seen here. If you live in the USA, then you live in Florida, because obviously you could also live in Texas, or California, and many other places. Lastly, it should be noted that if you see a flaw question with confusing the sufficient condition with the necessary condition, or anything equating to that idea, then there needs to be a conditional somewhere. If there is no conditional, then that answer choice will be wrong. But be careful, if-then statements can be well hidden. Absolute vs. Relative. This is a rare flaw, but does come up occasionally, and the best way to describe it is through an example. Let us say you have a store, and you sell business suits. And you have two types of suits, custom made suits and factory made. The custom made suits are labor intensive, and therefore the profit margins are only 10%. On the other hand, the factory made suits have 25% margin, but all sell below $500. While the bespoke suits sell at any price point. Someone might make the argument, oh, 25% margin is so much better than the 10% margin, therefore you should only sell the factory made suits. But that is bad. Can you spot the error? The issue is relative vs. absolute. Yes, you can get better margins with the factory made suits, but if the custom made suits are, let us say, $5,000, then in absolute terms, it will beat out the other suits, since you have a profit of $500. Next, we have ad hominem. Ad hominem arguments are direct against the person, rather than the actual argument unto itself. These can come in many different flavors, such as the person making the argument is a bad person, and therefore they are wrong. Or maybe they are a hypocrite. A smoker might advise a younger person to never start smoking, and make an argument detailing his position. And even though he is hypocritical, he is still correct. One more example. Pretend there is an executive at a pharmaceutical corporation, who states his new drug will revolutionize the industry, One might argue that this executive has a vested interest, and therefore he is wrong. But, although he might have a vested interest, he might be telling the truth. It's not mutually exclusive. A better conclusion is that we should be wary of any of his statements, but stating he is wrong or a liar is a step too far. False equivalents. Have you ever heard of the expression comparing oranges to apples? Well, that is alluding to a false equivalence. Basically, if two items are closely related, but not exactly the same thing, then it is wrong to equate them as identical. Here is an example argument. The alpha diet led to a greater weight loss than the omega diet in our study using a random sample of 500 participants. Therefore, anyone who wants to lose fat should do the alpha diet. In this case, they are equating the terms weight and fat, which are closely related, but not exactly the same. Weight does not need to be fat. Instead, it could be water rate or even muscle, so the conclusion does not follow from the premise. Some other examples which are found on the LSAT would be creating wealth and income. Wealth and income both deal with money, but are a bit different. One more comparison would be a meteor and an asteroid. It's easy to see the difference now, since we are using simple examples, but it is harder on the LSAT, since the questions are wordy. To fix this, read slowly. Think about each term in each sentence, and see if they transition to another term that might be a bit different. Circular reasoning. This flaw is like its namesake. It is going around in circles and circles. A good argument has a conclusion, which is then supported by a premise or premises. In a circular argument, you are assuming the truth of the conclusion in the premise and never actually proving anything. It would be like saying, oh, that guy is guilty of murder. Why? Well, look at him. He is obviously guilty, since he did it. A better argument would be he is guilty, since we found his fingerprints at the crime scene, or there was a witness. The previous circular argument is just assuming guilt and never provides any support. This fallacy is actually pretty rare on the LSAT for whatever reason, but once in a blue moon, it does show up. Whole to part. Whole to part, or also known as part to whole, is a common flaw on the LSAT. This flaw is predicated on making a proper inference from the whole of a certain property to its respective part, or vice versa. This definition could be abstract, but an example shouldn't clarify any confusion. In a certain time and place, there is an estate sale from a well-known wealthy self-socialite and art collector. The estate is worth countless millions. Susan argues it would be pointless for her to go to the estate sale, since she is not a multi-millionaire and could not afford any of the items offered. But her logic does not naturally follow. Even though the whole collection is expensive, and the keyword being whole, does that mean each part of the collection is expensive? There could be one piece or more that is reasonably priced. You just don't know. Inadequate argument. In everyday language, the meaning behind an inadequate argument is straightforward, but its precise use and application in the LSAT can be difficult at first. For these, an argument is given, the evidence outlined is then refuted, and that in turn is used improperly to disprove the conclusion. This might sound fine and dandy and not a flaw at a quick glance, but we can look at an example to see why this is not the case. Bob is a great guy, since he gave a million dollars to charity. You are wrong. He never gave a million dollars to charity, thus he is not a great guy. Basically, the person making this argument is saying Bob is not a great guy. Why? Because his inadequate argument, due to the fact that the premise outlined in support of Bob being great, is in fact incorrect. But, even if that was true, we still can't conclude that Bob is not a great guy. Perhaps he is a great guy for other reasons. Maybe he adopted an orphaned kitty cat? Or gave $100,000 to charity, which is still a lot of money. A better argument would be we need to do more research to see if this dude is really great. But the error is swinging the pendulum too far, stating he is not great is going too far. Cause, effect, and correlation. Have you ever heard of the expression that correlation does not imply causation? If so, then you are well versed in one aspect of causation that is found in the LSAT. There are many different types of causation flaws. Here are some core ones. If it is ever implied that A causes B, then you have to question it and ask if that is necessarily true. There are different explanations. Perhaps B causes A. Or, there is a third factor and this third factor, let's call it C, in turn causes A and B. Or maybe there is no causation. It's just some random coincidence. So, basically a correlation, but no causation. Here is a real world example. People take Advil tends to have headaches. Therefore, stop taking Advil to avoid any future headaches. This is obviously fallacious. The argument is implying that Advil causes headaches. But it is the reversal. People who have headaches tend to take Advil. So, basically they are stating that A causes B, but actually it is the reverse. B causes A. False dichotomy. This is a mouthful and might be confusing, so let us define it. Dichotomy can be defined as a division or contrast between two things that are or are represented as being opposed or entirely different. With a false dichotomy, we are presented with a situation where it is assumed there are only two possible choices, but in actuality there may be other options as well. We will start with the good argument. To get into law school, you need a GRE or LSAT score. She never took the GRE, yet she is in law school. Thus, she took the LSAT. There are one of two required options for the scenario. Thus, the conclusion logically follows. Once again, good argument. Here is a similar argument, but a bad one. Being a lawyer doctor provides a good life. She definitely does not want to be a lawyer. So, if she wants the good life, she will have to be a doctor. This is wrong, since these are not the only two options that lead to a good life. Maybe she can become an engineer, an entrepreneur, a superstar, or just the old-fashioned way of inheriting a boatload of money. Remember the LSAT trying to trick you into thinking there are only two options, but the flaw is that there are more than two options. Unrepresentative sample. This flaw deals with a sample that is not representative of a certain population. If we were to conduct a poll of college students and ask them do they have children, we might get a result that states around 3% of them have children. One might conclude that only 3% of adults have children. This is obviously ridiculous. Most people have children later in life. Therefore, the sampling is biased or unrepresentative. You should ask the general population, not a specific cohort. Improperly predicting the future from past events. There's nothing wrong with predicting the future. Economists do it, pollsters do it, CEOs do it, and even you do it. The question is when is it a fallacy? This flaw is treating past events as absolute and will always be the case while ignoring the fact that things do change. Now is the time for our example. Our company has always had men as the CEO. We are searching for a new leader. Although Susan is a great candidate, she will not be our next CEO since all the previous ones were male. This is a ridiculous argument just because it has always been a certain way does not mean it will always be the case. Times change and the world changes as well. Gambler fallacy. This is a common flaw for gamblers, hence the name, but also shows up in the LSAP. For example, we can think of roulette, which is a casino game where a ball spins around and lands on a color and a number. If the ball lands on red four times, then one might be tempted to say that it is now more likely to land on black, but that is not the case. It's still around a 50-50% chance of landing on red or black. The past results do not alter the odds. There is one caveat though. It is an extreme case. If the ball lands on red, let's say, 90 times in a row, then the odds of that are so astronomical that we can safely conclude that the game is rigged and therefore is in fact more likely to land on red. This idea does not really come up on the LSAP, but it's good to explain this fallacy fully and list out the limitations. That is it. Hope you found it helpful. There might be one or two flaws that we did not go over, which are the super rare ones, but we'll make a second video to cover these soon. Yet, this video covers 99% of the flaws and should give you all the tools to succeed on these questions and the LR section.