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Not sure what all those letters and arrows are that people draw for the LSAT? Watch this video on Sufficient and Necessary Conditions, fundamental to LSAT Logic.

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Drawing LSAT Sufficient And Necessary Conditions

LSAT Penguin Logic

This doesn't involve logical arrows, but it's funny.

You've probably heard a lot about sufficient and necessary conditions on the LSAT. They're tough to get a handle on at first, but not that difficult once you get the hang of it.

A sufficient condition is "enough" to tell you that something else is true. Suppose I tell you that a CEO of a fortune 500 company is powerful.

Then if I tell you that Tim Cook is CEO of Apple, a fortune 500 company, you know something. Tim Cook is powerful.

A necessary condition is something that has to be true, when something else is true. "Powerful" is the necessary condition of the statement I just told you. If you find out that Marissa Mayer is CEO of Yahoo, then you know she is necessarily powerful. It can't be any other way.

A conditional statement has a sufficient and a necessary condition. A conditional statement is true 100% of the time.

So if I tell you that all Fortune 500 CEOs are powerful, don't look for an exception. Just assume that it's true. This isn't a good idea in real life, but it's what you have to do for the LSAT.

Drawing LSAT Conditional Statements With Arrows

It's complicated to try to keep track of several conditional statements. And LSAT logical reasoning questions often give you several conditional statements. So you should use a system of shorthand notation to represent them.

The system everyone has settled on has letters and arrows. Take the statement I gave above. Here's a good way to draw it:

C --> P

I prefer to stick to one letter, or two at most. Some people will try to add more letters, like this:

CEOF500 --> Pow

That quickly gets confusing. The letters should serve as a reminder of the statement, but they don't have to mirror every part of it.

Joining Conditional Statements To Form Deductions

If you have multiple conditional statements, you can often join them. Anytime the necessary condition of one statement matches the sufficient condition of another, you can put them together.

example: 

"Every CEO of a fortune 500 company is powerful."

"Everyone powerful is a little arrogant"

C --> P

P --> A

C --> P --> A

"Every CEO of a fortune 500 company is a little arrogant"

You could also draw this as C --> P --> LA, if you prefer to include the "little" in the statement about "arrogant".

Did you like this lesson on LSAT conditional statement diagramming? If so, you'll enjoy our online LSAT course, which has complete lessons on LSAT logic, applied to real LSAT questions.

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[This is a lesson excerpt from our online LSAT course, for which we invite you to enroll.]

19 common, repeated argument flaws that students overlook on Logical Reasoning

Note: This list is not meant to be exhaustive. It is simply meant to be a guide to the more common argument flaws the LSAT tends to exploit.

1. Attacking the source of the argument

To attack an argument you may attack:
1) the premises (which never happens on the LSAT); or
2) the support the premises give to the conclusion

What you DO NOT get to do is to attack the author, his past acts or arguments, his motivation, where the argument comes from, or anything other than (1) or (2).

2. Uses terms unclearly/equivocation

The author uses a term (with more than one meaning) inconsistently.  For example, “public interest” in one sense means what is in the best interest of the public (e.g., clean air, roads, schools).  In another sense, it means what the public is interested in (e.g, celebrity gossip).  The shift in word meaning will often be subtle and hard to notice.

3. Analogies that really aren’t analogous enough

All arguments by analogy fall apart at some point.  At some point the two things being analogized lose their relevant similarities and the analogy cannot continue.  We can say attacking the LSAT questions is like attacking enemy starships.  But, in many ways, it’s not.

4. Appealing to authority in an area outside their expertise

Appealing to an authority where the subject matter is outside the expertise of the authority. For example, a dentist’s opinions on automotive maintenance is not authoritative.

5. Causation confusions

Whenever the LSAT concludes or assumes that A causes B, 99.9% of the time it’s wrong. They’ll tell you A is correlated with B or that A coincided with B and therefore A caused B.  Maybe.  That’s just one possible explanation for the correlation. Here are the other 3 possible explanations:
1) B caused A
2) C caused both A and B
3) A and B are merely coincidentally correlated and really something else, X, caused B.  We see this a lot with accident rate and speed sign questions.  New speed limit sign was put up!  Accident rates drop!  Therefore, it must be that the new speed limit sign dropped the accident rate.  Maybe.  But maybe there was an increase in cop cars patrolling the area and that’s what actually caused the drop in accident rates.  The speed limit sign was just coincidentally there.

6. Circular reasoning

Assuming what you’re trying to prove.  The premise is a mere restatement of the conclusion.

“Everything I say is true. This is true because I said it, and everything I say is true.”

7. Confusing necessary and sufficient conditions

The oldest trick in the book.

8. False dichotomy

A false dichotomy only pretends to divide the universe into two binary halves.  It is not a real contradiction.  Consider this real contradiction: cats and non-cats.  That’s cleanly cuts the universe into two halves.  Garfield?  Cat.  Einstein, MacBook Pro, Love? Non-cat.  Here’s a false dichotomy: Cats and dogs.  See how that leaves out Einstein, MacBook Pro, and Love?  They are neither cats nor dogs.

9. Confusing probability for certainty

Could be is not must be. Even if something is 99.99% likely to happen, it does not mean that it will happen.

10. Confusing is for ought

Don’t confuse the descriptive for the prescriptive.  Descriptive simply describes the state of the world.  The tree is small.  The lake is murky.  Prescriptive reveals values.  The tree ought to be big.  The lake should be clear.   The prescriptive reveals what we care about.  You will typically encounter a descriptive premise leading to a prescriptive conclusion.  For example, the house is on fire therefore we should put the fire out.  That’s not a good argument.  There are a number of reasons why we wouldn’t want to put the fire out.  We always need a bridge premise to take us from the descriptive world of the premises to the prescriptive world of the conclusion.  The bridge in the example argument above would be: Houses that are on fire ought to have their fires put out.

11. Percentages v. quantity

Percentages don’t necessarily reveal quantity and vice versa.

For example, Group A wants a 10% raise and Group B wants a 50% raise. Who will earn more money afterward? Who is asking for more money? We have no way to know based on this information.

12. Surveys and samplings to reach a general conclusion

Remember that surveys and samplings must be random (that is, non-biased). Asking a group of 20 year olds about who they are voting for will only tell you who 20 year olds are voting for (assuming they’re a statistically random set of 20 year olds regarding race, gender, etc.), not who the entire country will vote for.

13. Hasty generalization

Hasty generalization is very similar to sampling error. The difference is that the conclusion is very broad. You cannot make a generalization based on small sample size or based on one or two incidents.

14. Experiments to reach a general conclusion

Experiments to reach a general conclusion must include a control group.  It must also establish the baseline of what is measured before the experiment begins.

15. Your argument fails therefore the opposite of your conclusion must be true

Be careful of arguments that try to do this.  Just because you’ve wrecked someone’s argument, doesn’t mean that you get to conclude the opposite of his conclusion.  If I make a crappy argument for going to the movies tonight as opposed to going to a bar or doing any number of things, you can’t just show me why my argument sucks and conclude: therefore we should go to a bar. First of all, there could be other arguments made to support going to the movies.  Additionally, you still have the burden of making an argument that proves that we should go to the bar.

16. Relative v. absolute

A is faster than B, therefore A is fast? Not necessarily so. A is faster than B in relative terms. It doesn’t imply that A is fast in the absolute sense. For example, we know that that the conclusion in this statement is not true: “Hippopotamuses are smaller than an elephants. Therefore, hippopotamuses are small.” Or take this statement: “Turtles are faster than ants. Therefore, turtles are fast.”

17. Confusing one possible solution for the only solution

There are many ways to solve a problem. Just because one solution solves a problem doesn’t mean that particular solution is the only solution that can solve the problem. Nor, for that matter, does it mean it is the best solution. If I nuke Cleveland, I’ll probably solve Cleveland’s homeless problem. This does not make it a good solution.

This flaw can also be used in the negative. This happens when one solution to a problem turns out not solve the problem, and then the conclusion might say that the problem cannot be solved or that the problem shouldn’t be solved. The flaw remains: just because one solution to a problem is inadequate doesn’t mean that the problem itself cannot be solved.

18. Red herring

This happens when the argument doesn’t address the relevant issue.  Rather, it addresses some other issue that is tangential or has nothing to do with the relevant issue but, for some reason, commands your attention.

19. Tradition fallacy and novelty fallacy

The fact that something is old doesn’t mean that it is right or better. In the same vein, just because things have been done a certain way for a long time doesn’t mean that it is right or better. See slavery.

Likewise, just because something is new doesn’t entail that it is best course of action. Nor does it entail that the old thing or idea is no longer relevant or true. Change for the sake of change is not an argument; there must be something that shows the change is better.

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Did you like this list of common LSAT argument flaws? You'll find more information like this in our online LSAT course, along with walkthroughs of hundreds of flawed LSAT arguments.

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[This is a lesson excerpt from our online LSAT course, for which we invite you to enroll.]

Logic games are the hardest section of the LSAT, at first. They're like nothing you've ever seen before, and they're very confusing.

Fortunately, they're also the easiest section to get better at. It all starts by getting a good overview of what you're up against. That's why we made this video introduction logic games. Enjoy!

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You may find logic games tough now. They're difficult because they're unfamiliar. As you practice, they get a lot easier. We promise.

Repeating logic games until you master them is the best way to get good at games. Our students have used repetition to score near perfect on games, and so can you.

Don't worry too much about game types. You'll find complicated classification systems in books and on the internet, but these aren't necessary and can be distracting. We just classify games as either sequencing, grouping or a mixture of the two types.

Did you like this introduction to logic games video? It's part of our online LSAT course. If you found the video useful, you'll probably like the rest of our course too. You should have a look.

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The LSAT is hard.  There’s no getting around that.  But it is a learnable test.  You can study for the LSAT and improve in a pretty dramatic way.  Study hard and study right, and you will get better at the LSAT.  There are three things you need to do to get a great LSAT score.

1. Master reading and logic

The LSAT is a test of reading and logic.  Read that again.  If you get good at reading and logic, you get good at the LSAT.

Reading?  Yes, really.  Reading.  The language used in the LSAT is confusing, yet precise.  The LSAT tests your ability to parse and decipher complicated sentences.  Sentences with words you never heard of, triple negatives, and clauses within clauses.

Let this sentence be a warning if you never thought that lack of grammar understanding impacts how many students do on the LSAT in a negative manner and you don’t find yourself seeing that it’s not unclear from this sentence that it actually has such an effect.

After reading, you need logic.  Once you actually understand what the questions and answers say, you have to understand how the logic plays out.  Concepts like validity, conditional statements, and premises should be near and dear to your heart.

How do you get good at logic?  For starters, try to take courses like Introduction to Logic, or Formal Logic in undergrad.  But really, a good LSAT prep course will teach you all the logic you need for the LSAT.  If they don’t teach you logic, then they’re robbing you blind.

2. Practice until you want to stab your eyes out with a No. 2 pencil

Take as many real, timed, LSAT PrepTests as possible. There are enough old LSATs (over 70) available that you will lose all your friends before you finish all of them.

Take only real LSATs.  Most LSAT books that you see in the bookstore do not use real LSATs. They make up their own questions to avoid licensing fees.  Made up LSATs are a complete waste of time.  Stay the hell away.  The whole point of practicing is to get good at doing the LSAT, not Honest Sal’s LSAT-like Test.

3. Review your answers

So once you finished a practice exam, what’s the first thing you do?  You check the answers and grade your test right?  No, wrong.

You should do something we call “Blind Review”.  When you take the practice tests, you circle every question you are unsure about.  After the test is over, go through every one of those questions and take however long you need to on the question – without looking at the answer.  Then when you mark your test you will have two scores.  Your real score, and your blind review score.  If your blind review score is low, then you need to work on your reading and logic.  If your blind review score is high, then you need to work on your speed.

This is a powerful way of learning that only works when you haven’t peeked at the credited answer!

What now?

So now you know the three things you need to do in order to do well on the LSAT.  If you want to test the waters, sign up for a free trial.  If you're ready to dive in now, register for the best and most affordable online LSAT Prep course you can get.

What are you waiting for?  Jump in, beat the LSAT, go to law school and become a lawyer.

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One of the most common questions we get is how to improve at LSAT Reading Comprehension. It seems really tough to do: either you are good at reading, or you're not, and you can't do much to change that, right?

We disagree. Here at 7Sage we've been testing a new approach to Reading Comprehension that has gotten great results, and now we're proud to present you with: The Memory MethodTM for Reading Comprehension.

Train Your Memory For LSAT Reading Comprehension

Ever read a passage, then feel like you don't remember anything? You get to the questions and realize it's true: you've forgotten most of what you read.

It happens to almost everyone. We're not built to retain all the information presented in a reading comprehension passage. But you can get better.

The drills in this post build your mental muscles, and will teach you to retain what you read when you take a test.

This method will teach you to do what skilled readers do naturally: consciously think about what you're reading.

The Memory MethodTM For Reading Comp

These are drills to be done with individual reading comp passages. Do these drills with 6-8 passages.

It may be tough at first, especially the "Check Your Memory" section. But if you stick with it you'll learn to retain what you read.

Phase I - Improving Retention

Memorize The Passage Structure [3.5 Minutes]

1.Take a passage. Spend 3.5 minutes reading it.

2. At the end of each paragraph, summarize the main point of that paragraph into one line.

3. At the end of the passage, look over each paragraph again and make sure you know the main point. Combine these main points into a narrative.

4. Once you know the point of each paragraph, decide on the main point of the passage.

Gaining command of the passage will speed you up when doing the questions.

Check Your Memory [1.5 Minutes]

1. Turn over the passage - don't look at it.

2. On a sheet of paper, write down the main point of each paragraph (one line each), and the main point of the passage.

RC tests whether you really retained what you read. If you don't remember anything at first, don't worry, and don't look back at the passage.

Just write down what you do remember, and resolve to do better next time.

Do The Questions - Avoid Time-Traps [3.5 Minutes]

1. Turn the passage over, you can look at it again.

2. If the question involves a specific detail (e.g. lines 17-21, paragraph 2, the statements of Picasso and Braque), reread that section of the passage. This shouldn't take long, because you memorized where details are located.

3. If there is no specific detail, attempt to answer the question.

4. In either case, if you think one answer is right, use your gut and move on.

5. If you're not sure, refer back to the passage [but be quick about it].

6. If step 5 doesn't solve it, flag the question, pick an answer, and move on.

If you waffle between answer choices, then you are spending most of your time on the hardest questions. This is a time-trap. You want to spend your time on questions you can solve.

Give each question an honest shot. But if you aren't getting it, cut your losses and move on to the other, easier questions.

Eventually, you will get fast enough to come back to the flagged questions with a fresh mind. They're often significantly easier the second time through.

Phase II - Reading Comprehension Mastery

The second phase of the memory method is exactly the same as the first, with one exception: you only spend 30 seconds on step two (Check Your Memory).

Do this 6-8 times. The first phase teaches you how to retain information. The second phase teaches you to quickly recall and apply it.

Conclusion - Practice, Practice, Practice

Getting good at LSAT Reading Comprehension is a habit. These drills lay the foundation for proper technique, but you'll have to revisit them from time to time to perfect your method.

If you feel your retention flagging, focus on improving it. A good command of the passage and it's structure is the key to success on reading comprehension.

If you liked this blog post, you'll find even more good reading comprehension advice in our online LSAT course.

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[This is a lesson excerpt from our online course, for which we invite you to enroll.]

The June 2016 LSAT administration is on the horizon. Student after student has been asking us: "Should I take the LSAT in June or delay it to the next (September 2016) administration?" Let’s help you evaluate your situation and make a decision, with a reality check.
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[This is a lesson excerpt from our online course, for which we invite you to enroll.]

A video introduction to LSAT logical indicators.

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Sufficient And Necessary Indicators On The LSAT

LSAT Necessary Or Sufficient Condition?

Sufficient Or Necessary?

 

The words in the 4 translation groups, which are covered in our online course, and the words “some” ”most”and “few” (which are also in lessons in our course) are special. They are logical indicators. Also called logical operators. As logical indicators, these words perform a very specific function in the English language. They lay down the structure of the sentence as opposed to the content.

For example, let’s consider “if”.

I can say, “If you are a man, then you are mortal.”
Or I can say “If you like cheesecake, then you’re gonna love my surprise!”

Of course, these sentences are distinct. They express very different ideas. The first sentence is about the inevitable mortality of all men and the second is about cake. But, these different ideas are not informed by the words “if” and “then.” Rather, they are informed by the other words in the sentence, like “mortal” and “cheesecake.” What do “if” and “then” do? They lay down the structure of the logical relationship. In other words, what they do is to establish that whatever these ideas may be in this particular sentence (in the first example, being a man and being mortal, in the second, liking cheesecake and liking the surprise) they exist in a conditional relationship with each other where the idea following the “if” is the sufficient condition and the idea following the “then” is the necessary condition.

Once you realize this, you see that it doesn’t matter what ideas go into this structure. If X then Y says that X is sufficient for Y and Y is necessary for X. You can define X and Y to be whatever you want. X is being a man and Y is being mortal. So we’ve recreated the first sentence. X is eating a hamburger and Y is being able to fly. So, eating a hamburger is sufficient for being able to fly. That sentence would, of course, be false. Awesome, but false. Yet, that doesn’t change the fact that it expresses a conditional relationship between the two ideas. Of course, the reason that it’s false is because that conditional relationship does not hold in our world. Who knows, maybe there is a world where eating hamburgers guarantees your ability to take flight. That world will be almost as crazy as one in which being a Jedi allows you to use the Force, whatever that is.

LET’S REVIEW
Some words in English express logical relationships. We call them logical indicators or logical operators. These words are special and you should train to become sensitive to them.

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[This is a lesson excerpt from our online course, for which we invite you to enroll.]

Below, you will find a LSAT logical reasoning question with each of its components labeled. Learn their names. You will not be able to follow along with the curriculum if you do not know what the different parts of the question are called.

I also want to introduce you to “the author.” The author is the person writing the passage to you. It’s helpful to think of the author as the person speaking to you, trying to convince you of her point of view, in other words, trying to sell you on her conclusion. In the curriculum, I will often refer to the “author’s argument” as “our argument” or the “argument.” Take note of this when it happens. Often, the stimulus contains more than one argument and it’s invariably the author’s argument that the question stem is referring to.

LET’S REVIEW
The author is the person writing the passage to you. The passage is the same thing as the stimulus. The question stem lays out the directions for you to choose the correct answer choice.

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First, a word of caution:

The honest truth is that for the vast majority of students, low scores are not properly attributed to LSAT anxiety, because the vast majority of students have large gaps in their fundamentals that have nothing to do with nervousness. Your mindset counts for a lot, but you can’t relax your way out of knowing how to take a contrapositive.

If you’re looking to improve your score generally, the curriculum is this way. If you’re looking to ensure that you can apply what you’ve learned correctly on test day and hit the same range of score that you’ve been hitting in practice, then keep reading.

1. Interpret your bodily reactions differently

Let’s say that you get the butterflies every time you look at the cover of a fresh LSAT practice test. Rather than interpret those butterflies as nervousness, train yourself to interpret those butterflies as excitement, a sign that you’re about to do something awesome. This has two benefits – it avoids the nervous thoughts, and it puts your mind into a positive mindset.

2. Put your fears on paper

Also known as “Flooding Therapy”, this is a great way to alleviate stress. The key to this technique lies in the fact that your brain interprets your thoughts differently once they’ve been expressed concretely, versus just floating around in your brain. You know those times when you just have to get something off your chest? Yeah, it’s basically that. This technique has been used with varying degrees of success with Post-Traumatic Stress Disorder patients, so it’s probably more than powerful enough for even the most test-anxiety-crippled LSAT taker.

To do this, simply sit down for about 10 minutes or so before you take a practice test and make a list of all the things that you’re worried about. It can be as large scale as thinking you’re going to flat out bomb the test, as detailed as thinking that you missed 15% of your flaw questions on the last test, which is higher than your usual 12%, and you’re scared that it might get worse, or as seemingly irrelevant as you thinking that you don’t look very presentable on this particular morning. Whatever it is, get it out. One study showed that a 10-minute “emotion-dumping” session led to a 15% increase in performance over a control group that just went through their normal pre-test routine.

3. Meditate!

The goal of meditation is to train your mind to block out distractions. We’re not just talking big distractions, either – while the ability to focus while sitting next to the guy who blows his nose every 4 seconds is a nice side bonus, it’s not the main thrust of the exercise. The goal is to be able to focus through the more subtle things that creep into your mind – in particular, the thoughts of doubt and worry that sabotage you while you’re busy trying to take the test.

You should be entirely awake and alert during the process of meditation – this is not an excuse to take a nap before you start a test. Close your eyes and focus on something. Focusing on your breathing is great since it’s readily available. Don’t let any other thought enter your head. If you find your mind wandering, give yourself a mental slap on the wrist, push those ideas out of your head, and return to focusing on your breathing. Do this for ten or fifteen minutes at a time, twice a day if you can manage it.

This will be exceedingly difficult for the first few weeks, and you will probably be pretty bad at it to start. Eventually, though, you’ll begin to notice that your mind wanders less and less. This is the mental training that, down the line, will enable you to push aside those feelings of doubt and worry and focus your entire attention on beating the LSAT.

4. Positive Self-Reinforcement

One of the simplest and most effective ways to get all those feelings of doubt and worry out of your head is perhaps the most obvious one – just remember how awesome you are! By the time test day arrives, you should know exactly what you can reasonably expect to score, so why allow the doubt to creep back in? Test day is neither the time nor the place. Remembering that you’ve been hitting your target score consistently for the past month and a half goes a long way toward squashing your nervousness. Remember your highest score, remember that time you wrote a perfect logic game section, remember that time that you got every flaw question on the test right – remember SOMETHING that will remind you that you can conquer the test in front of you.

5. Practice under mild stress

Practicing under stress doesn’t necessarily have to mean that you should have the weight of the world on your shoulders every time you take a test. Actually, all that really matters here is that there is something – anything - at stake. If you adhere to a practice test schedule, odds are that you already put some amount of pressure on yourself to do better the next time. Unfortunately, there’s no real pressure to perform and no immediate consequences to doing poorly in practice (except perhaps a slight ego hit). And you’d better believe that on test day, when so much is at stake and the consequences of doing poorly are very real, you’ll be feeling the pressure to perform.

So, create your own consequences. For example, maybe you can put a quarter in a jar every time you miss a logic game question, or maybe you can do five pushups for every logical reasoning question you miss. No matter how trivial the stakes seem, the fact that your performance now has real consequences attached to it on a day-to-day basis will train your brain to function under stress.

Again, I must reiterate – none of this replaces real understanding of logic, and you still have to make sure that your actual LSAT capabilities are on point to do well on this test. That being said, if you get nervous when thinking about test day and you want to avoid a big letdown, try one (or all) of these things, and stick with it. By the time test day rolls around, you’ll have trained your mind to dispense with the worry and the nervousness, leaving you free to rock the LSAT to your fullest capabilities. The rest, as they say, is up to you.

Good luck!

Jonathan Wang is a professional LSAT tutor and featured instructor for 7Sage.

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[This is a lesson excerpt from our online course, for which we invite you to enroll.]

IT HAS BEEN SAID THAT “ALL JEDI USE THE FORCE.”

For this edition of LSAT Fundamentals, let’s engage in a little verbal sparring. Say the above sentence differently. By that I mean use a different grammatical structure to express the same meaning. Give it a shot, young Skywalker.What? You are done already? Let me see what you got there.

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