Playing with a Full Deck

Countless successful students prove that people can see significant and sustained improvement on the LSAT over time. That’s great for them, but how can you get such results? Here is how I use index cards and the “blind review” process to help my students get the score they want.

There are lots of LSAT prep materials (PowerScore, Kaplan, Princeton Review, etc.). which range from “brief but useless” to “overlong and overwhelming.” You can buy a 900 page book that is “guaranteed” to raise your score, but the book won’t actually help you until something in that book enables you to eliminate a wrong answer or choose a right answer. If you’re lucky, those 900 pages might contain thirty concrete and specific insights or techniques that consistently affect your score.

I never require my students to buy any specific prep materials. I want them to make the most of whatever they start with, whether they come to me with the LSAC “SuperPrep” or the entire PowerScore LSAT Bible Trilogy. Instead, I help them figure out generally-applicable techniques that enable them to eliminate a particular wrong answer or identify a particular right answer, and write it out on my tutoring whiteboard in a format that would fit on an index card. At the end of each session, I expect them to save those whiteboards and copy out any new cards and add them to their personal card deck.

Once you have some cards in your personal deck, I will ask you to do one logical reasoning section under time pressure. For students who are already scoring at or above the national average (152), that means under 35 minutes. I don’t put a specific time limit on students who are still scoring under 152, but I do have them time each individual question with a stopwatch.

Once you complete that logical reasoning section under time pressure, don’t score it! You have completed the “testing” phase of the process, but you haven’t even started the “learning” phase. The next step is to “blind review” each question, using your personal card deck. Let’s walk through that process, using Section 2 of the  June 2007 LSAT (which is the only test that the LSAC makes generally available).

Question 1: Which one of the following most accurately expresses
the main conclusion of the economist’s argument?

Process: Do I have an index card for this? No, I don’t, because I usually get main point questions right. Looking at my test paper, I see that I originally underlined the phrase “not all efforts to increase productivity are beneficial” because it looked like the conclusion to me. I know that the conclusion is the phrase that everything else in the paragraph supports, and that’s true here. The answer I chose was B, which says,”Some measures to increase productivity fail to be beneficial.” I’m pretty sure that “Not all are” is logically identical to “Some are not,” so I’ll stick with my original answer. Since I double-checked my reasoning, I’m going to take my ball-point pen and draw a blue circle around the black pencil circle I started with. 

Question 2: Which one of the following uses flawed reasoning that
most closely resembles the flawed reasoning used in
the argument above?

Process: Parallel flaw–let’s see, I do have an index card for this one.

Parallel flaw: read the stimulus and see if you can spot the flaw.
If you can see it now, you can do it now.
If you can’t see the flaw, this will take longer than any other question and you’re still likely to get it wrong. Save it for last!
If you still haven’t seen the flaw, read the answers CAREFULLY. One of them has the hint you need.

Well, that’s good–because I couldn’t see the flaw with the clock ticking and I still can’t see it. Let’s look at the answers for hints. Nothing in A… B is interesting. If I mix something extremely toxic (like arsenic) with something non-toxic (like water), I’ll bet it’s still extremely toxic, not “moderately toxic.” That’s sort of like the stimulus–breeding a dog that barks a lot with a dog that doesn’t bark won’t necessarily give you a moderate barker. Let’s circle B with the blue pen. Since this card seems to have actually helped me here, let’s put a little tick mark in the top right corner of the card. 

Question 3: Which one of the following most logically completes
the argument?

Process: This looks like some kind of inference. I have a card for that.

1. Pick an answer.
2. Could the opposite of that answer ever happen?
3. Reread the stimulus–if the answer you picked CAN’T BE FALSE, you’re right!
4. Avoid answers that COULD BE TRUE, answers which reference something you have no information about, and answers which are EXPLANATIONS of the stimulus rather than DEDUCTIONS from it.

I picked answer A, “people at a century’s end reminisce about their own lives.” Could that ever be false? Maybe. I mean, some people may look back on their own lives but others wouldn’t. A might be wrong. Let me look at the others. B looks wrong–no information about fearing. C talks about looking forward to the next century. That COULD be true, but it doesn’t have to be true. D talks about the history of the century just ending. Could that be false? People don’t care about the century just ending, but the stimulus says that people behave toward the century much as a person behaves towards his or her own life. If we look back at our lives at the end of a century, I guess people at the end of a century must look back on the century. OK, let’s circle D in blue, and add a tick mark to the card. (Hmmm– that’s the fifth tick mark on this card. I guess I should be thinking about this while the clock is running–I want to  get this question right the first time, not just on blind review!)

Question 5: The reasoning in the consumer’s argument is most
vulnerable to criticism on the grounds that the

Process: Flaw! OK, there’s a card for every different answer to a flaw question. Let’s look at these answers. A talks about  bias. I have a card on this.

Flaw: Bias.
This is a specific form of the more general ad hominem fallacy, which attacks the person rather than the argument.
Bias may show that a witness is unreliable, but it does not prove that the witness is lying.
Any conclusion that says the opposite of what the biased witness says is flawed.

Let’s see–answer choice A starts with the phrase, “treats evidence that there is an apparent bias.” Yes, the stimulus does do that. It goes on “as evidence that the Connorly Report’s claims are false.  Yes, it does that, too. Looks like a perfect example of an ad hominem fallacy, which is what I though the first time. Keep the pencil circle around A–I’m so sure of this one that I’m not going to put a blue circle around it.

Question 6: The argument’s conclusion follows logically if which
one of the following is assumed?

Process: I hate these! OK, I know it’s an assumption question of some kind, but what kind? I have a card here somewhere…

C->A                                                   A->C
Does the question include the word “if”? Probably “sufficient.”
Does the question include words like “rely,” “depends”? Necessary.

OK, it does say “if” in the question. “If I assume, the conclusion follows.” Looks like it’s a sufficient assumption. (Add a tick mark to this card.) Now, I know I have another card about that.

1. Find the conclusion. Look for a new term. It MUST BE in the correct answer.
2. Find any term that appears both in the conclusion and a premise. It should not be in the correct answer.
3. There should not be any brand new term in the correct answer–only something that has already appeared in at least one premise.

Right. So the conclusion here is “Murray cannot be accepted for the position of Executive Administrator. Good–Executive Administrator is a new term. Knock off all the answers that don’t include that term. Oh–that’s answer A, which is what I picked! Well, put a tick mark on this card–if I had remembered this I wouldn’t have chosen that. Moving on to step 2; “Murray” appears in the conclusion and the premises, so I guess I can knock out D and E. Rule 3 doesn’t help me choose between B and C, so I guess I’ve gone as far as the “Mechanistic Approach (TM)” will get me. Good thing I have another card here…

With MBT, MSS, MBF: the ANSWER can’t be false.
With SA, PSA: the CONCLUSION can’t be false if  you pick the right answer.

So–the conclusion here is still, “Murray cannot be accepted for the position of Executive Administrator.” With answer choice B, Murray can’t be on the executive board (because he  has a felony conviction), which means he can’t be Executive Administrator. That looks pretty good. With C, there’s nothing to keep Murray from being Executive Administrator. OK, C is out and B is in. Put a blue circle around B and add a tick mark to this card. (Hmm. That’s the first time this card has actually helped me!)

Questions 7-25… repeat this process until you finish the section.

When you (finally!) finish blind reviewing that last question, you’re ready to score the section. I encourage all my students to set up a free account at (which may well be the single most fabulous LSAT resource on the Internet). 7Sage makes it easy to bubble in your blind review results–there’s a black bubble for your initial answer, and then, if you click on the question number, another line of blue bubbles pops up so that you can add your blind review result. When you save and score your answers, you’ll see your score for that section (and the test as a whole). In addition. 7Sage will sort the questions into “very low priority,” “low priority,” “high priority,” and “very high priority” questions.

The “very low priority” questions are those you got right the  first time. For self-study purposes, these “very low” questions are unimportant. Since you already got it right, there’s nothing new to learn!

The “low priority” questions, by contrast, are very important. You got this question wrong under time pressure, but got it right when you worked through it with your card deck. Go over these “low priority” questions and take another look at the card that helped you get it right. Ask yourself, “What could I do different next time so that I get this right while the clock is running?” You already know how to get this question right–now you need to get it right the first time.

The “high priority” questions are also very important. If you have a card for this situation, it isn’t helping you yet. If you don’t have a card that helps you here, it’s time to get one!  I ask my students to look over these high priority questions and flag the question on 7Sage if they can’t figure it out on their own. At our next tutoring session, we’ll use those flagged questions to figure out which generally-applicable insight or technique would help you get it right.

Over time, we will build up an index card deck that enables you to get a blind review score that is consistently ten or fifteen points higher than your target score. At that point, you’re officially “playing with a full deck.” Then you’ll keep doing practice tests, using those cards over and over again until they’re second nature to you. You won’t be shuffling through your card deck on test day–it will be second nature to you.

Can you see sustained and significant progress on the LSAT? Yes, you can!

Flaw Questions

“Flaw” type questions come in three basic forms–assumptions, logical errors, and fallacies. Doing well on flaw questions means doing well on each of these three very different challenges.


Assumptions are easiest for people with no special training in logic. It is easy to spot an assumption type answer, since  it tends to start with a phrase like “fails to consider that” or “takes for granted that.” In a typical assumption scenario, the answer choice will provide a new fact that would make a big difference to the argument. You don’t need to be a logic whiz to figure out how that new fact might change things. Since each assumption-type answer is unique to the facts in that particular argument, there is no easy way to train up to do better on assumption answers.

Logical Errors

Logical errors, by contrast, do not involve new facts. They are technically known as “formal fallacies,” which means they are wrong because of the “form” of the argument. Any “formal fallacy” can be reduced to symbolic logic so that the actual terms under discussion no longer matter. A stimulus that says “Albion is in Britain” can be rewritten as “A->B.” In a “formal fallacy,” it doesn’t matter whether “B” stands for “Britain” or “Botswana.” For example, if I say “I am in Britain, therefore I am in Albion,” I have committed the logical error that PowerScore refers to as a “mistaken reversal.” To do well on this type of flaw question, you need to do well on conditional logic as a whole. I am working on a flashcard deck for logical errors.

  • Logical error flashcards

The third type of flaw is a specialized version of logical errors that cannot be reduced to symbolic logic. These “informal fallacies” involve a host of tricks and traps for the unwary. Unscrupulous people have been using these fallacies to dupe people for so many centuries that most of them have Latin names. These Latin names never appear on the LSAT, which adds an unintended degree of difficulty to the test. The LSAT answer choices that describe these informal fallacies can be more bewildering than Latin, especially to people who have some familiarity with the traditional names. To address this problem, I am working on two sets of informal fallacy flash cards–one that identifies all the most common and/or recent fallacies by their Wikipedia names, and another which then connects those names to wording that mimics the LSAT answer choices.

  • List of fallacies
  • Fallacy flashcards
  • Flaw answer choices

Informal Fallacy Flashcards

[qwiz] [i]

Informal Fallacies: This quiz identifies all the informal fallacies in 10 Actual Official LSAT Preptests Volume V. Since many fallacies have more than one name, we have chosen the name used by Wikipedia for each fallacy.

[q multiple_choice=”true”] presents a situation in which only limited alternatives are considered, when in fact there is at least one additional option.

[c]  Sampling bias

[f] No, that would involve some kind of survey error.

[c] Begging the question

[f] No, that would mean assuming what you are trying to prove.

[c*] False dilemma

[f] Good! 

[q multiple_choice=”true”]  infers that something is true of the whole from the fact that it is true of some (or even every) part of the whole

[c*] Fallacy of Composition

[f] Good!

[c] Argument from ignorance

[f] No, that would mean using a lack of proof as a way of proving something.

[c] May/Must Fallacy

[f] Wikipedia doesn’t know about this one–it is the error of saying something must be true just because it might be true.




The “Roll the Dice” Flaw

“Find the flaw” LSAT questions are both common and difficult. There are a lot of fallacies, and some of them are quite subtle.  The answer choices use “LSAT jargon” to describe each fallacy, not textbook Latin. That means you have to know the fallacy and the special LSAT terminology for it to answer the question with speed and confidence.

I recently ran across a “find the flaw” question that totally stumped me. I guessed one answer (with no confidence) on a timed test, then came back to blind review and picked another answer–still without any certainty. Both my choices turned out to be wrong, so I looked up the answer and promised to write a blog post about it. (I recommend this same procedure to students who want a 99th percentile score–you haven’t really mastered a question until you either know you got it right  or you write an essay about why you got it wrong.)

The question I had trouble with was PrepTest 65, Secton 4, #26. I won’t violate copyright by printing it here, so here’s a new problem with the same features. (If you own “10 Actual, Official LSAT PrepTests Volume V” you can find the actual question on page 143.

Nikola Tesla Magnet School accepts only the brightest students in our metropolitan region, so it boasts the best science club in the entire Tri-State Area. The best science club is most likely to win the annual robotics competition, so the Nikola Tesla Magnet School will almost certainly bring home the trophy this year.

I read this stimulus and immediately zeroed in on the difference between the best individual students and the best overall team. That’s such a common fallacy that it has a Latin name (“modo hoc“), although it’s not clear whether it applies in this case. But I never got that far because that wasn’t one of my answer choices. Here’s what was offered on the LSAT:

(A) presumes, without presenting relevant evidence, that an entity can be distinguished as the best only on the basis of competition.

(B) predicts the success of an entity on the basis of features that are not relevant to the quality of that entity.

(C) predicts the outcome of a competition merely on the basis of a comparison between the parties in that competition.

(D) presumes, without providing warrant, that if an entity is the best among its competitors, then each individual part of that entity must also be the best.

(E) concludes that because an event is the most likely of a set of possible events, that event is more likely to occur than not.

I was trying so hard to find a composition fallacy (that’s modo hoc for you Latin lovers) that I really wanted D to be correct, but it just wouldn’t work. I wound up picking C, then switched to A. B never appealed to me, and I never really understood what E was all about.

That was a mistake.

E is all about rolling dice. If I roll a pair of dice, seven is the most likely outcome. There are six out of thirty-six chances that I will roll a seven, making it more likely than any other roll (there’s a 1/36 chance of rolling two or twelve, a 2/36 chance of rolling three or eleven, etc., etc.). But just because seven is the single most likely roll, it’s not more likely to occur than not. I only roll a seven one out of six times. I’d have to roll it every other time (plus some) for it to be “more likely to occur than not.”

Most likely, but not more likely than not

That was my error. A science club may be “more likely” to win than any other club in the city, but that doesn’t mean it will “probably” win.

I’ve searched the Internet for the Latin name of this fallacy, and haven’t found it yet. You Latin buffs may refer to it as “alea jacta est.” The rest of us can just call it the “roll of the dice fallacy.”

Find the Flaw: A Difficult But Useful Skill

Some things you do to prepare for the LSAT are a waste of time as far as the rest of your life in concerned. Your ability to recognize a “parallel reasoning” question and skip over it until the end of the section is not going to help you be a better lawyer. But that is not true of all LSAT preparation. At least one area where you need to invest some significant time will serve you well throughout your life and legal career. That area is the “find the flaw” logical reasoning question type.

Logicians call these “flaws” fallacies, and diagnose them as carefully as doctors do diseases. If you take an old-fashioned logic class in an academic setting, you may still be expected to learn their Latin names, such as argumentum ad hominem, argumentum ad baculum, argumentum ad misericordiam, etc.

It used to be you couldn’t be a lawyer without knowing quite a bit of Latin, but aspiring lawyers aren’t expected to learn Latin anymore. That’s why the LSAT doesn’t give you Latin names in the answer choices. Unfortunately, the answer choices they do provide might as well be in Latin for all the good they do the brand-new test-taker. “Find the flaw” answer choices are worded in what I call “LSAT jargon,” a unique dialect found nowhere else on earth.

It isn’t that “find the flaw” answer choices aren’t in English, or that they don’t actually mean something. The problem is that an intelligent person can read the answer twelve times in a row and still not get what the test-writer is saying. Sometimes the only way to figure out what these answer choices mean is to look at the answer in the back of the book. Only after you see that “E” is the right answer will the fog clear and understanding set in. But by that time, you’ve already circled “C,” changed it to “A,” and beaten your head against a wall.

That’s the bad news. The good news is that LSAT jargon is no harder to learn than Latin, and the effort you make on this one question type will serve you the rest of your life. You will need to spot flawed reasoning in every contract you review, will you draft, deposition you take, or witness you put on the stand. On the LSAT, you have more than a minute to figure out a “find the flaw” problem. When your opponent is making her pitch to the jury, you have scant seconds; and when you explain your objection to the judge, you need to speak English, not Latin.

You might impress a jury by saying, “Your Honor, the counsel for the prosecution has committed a post hoc, ergo propter hoc fallacy,” but if the judge got his law degree in the last twenty years, you’re more likely to annoy him than persuade him. Try saying, “The State has confused a cause with a correlation, your Honor. Just because one thing happens after another thing does not mean it was caused by that other thing.” That might get your objection sustained and your client out of jail! And when your grateful client hugs you and hands you a check, you can say, “Don’t thank me–thank the LSAT!”