Flaw Answer Choices

[Foti]

Hi! I have a few questions that I would love some help and guidance with. There are a few different areas of concern so I will address them separately. Thank you so much for your time.

I understand flaw questions pretty well and I can spot the flaw quickly and accurately. However, often time the way the answer choices are worded confuses me and it takes me a while to decode what is being said in order to make sure that it is describing the correct flaw. This happens a lot when it comes to flaws dealing with conditional statements (mistaken reversal, mistaken negation etc) and also with cause and effect. I was once told that it safe to say that if I spot a nec/suff flaw then any answer choice that address any of those terms will be correct? I'm not sure if this is true, however. I feel as if I have seen an answer choice that describes mistaken negation and another that describes mistaken reversal within the same question. Was this advice true? If I spot the flaw, a conditional reasoning flaw for instance, and I notice language in the answer choice that identifies with that flaw can I safely choose it without wasting time decoding it? Could there be more than one answer choice describing two different conditional reasoning flaws?

This is an example, where I recognize the flaw but the wording confuses me:

It has been said that understanding a person completely leads one to forgive that person entirely. If so, then it follows that complete self-forgiveness is beyond our reach, for complete self-understanding, however, desirable, is unattainable.
Evidence: understanding --> forgiveness
Conclusion: ~ understanding --> ~forgiveness
Correct answer: Treats the failure to satisfy a condition that brings about a particular outcome as if satisfying that
condition is the only way to realize that outcome
Is this saying that if I were to take the contrapositive of the conclusion, forgiveness --> understanding that it works the same was as "if and only if" essentially? Either they both must occur or none of them occur? How is that the same as saying that is the ONLY way to realize the outcome, though?

When it says "mistakes...", "confuses...", "treats..." I get very boggled down by translating that. Do they all essentially mean the same thing? Is there any easier and quicker way to understand this particular wording?

I have made a list of flaw answer choices that correspond with the type of conditional flaw that occurs. Could you please let me know if I have added these answer choices under the correct flaw? It would help me more than you know.

Mistaken negation
 Taking the absence of an occurrence as evidence that a necessary condition for that occurrence did not take place
 Treats a characteristic known to be true of one class of things as if that characteristic were unique to that class
 Treats a characteristic known to be true of one class of things as if that characteristic were unique to that class
 Treats the failure to satisfy a condition that brings about a particular outcome as if satisfying that condition is the only way to realize
that outcome

Mistaken reversal
 Mistakes being sufficient to achieve a particular outcome for being required to achieve it (mistaken reversal)

Confuses a necessary condition for a sufficient condition
 From the assertion that something is necessary to a given goal, the argument concludes that that thing is sufficient for its achievement
 Confuses a result with a condition that is required to bring about that result
 Mistakes something that is necessary for a particular outcome for something that is merely sufficient for the outcome
 The argument confuses a necessary condition for species distinction with a sufficient condition for species distinction

Confuses a sufficient condition for a necessary condition
 Confuses a sufficient condition with a required condition
 Mistakes something that is necessary for a particular outcome for something that is merely sufficient for the outcome
 Treats a sufficient condition for the airport's being built as a necessary condition
 The author assumes that a condition that ensures a given result is required for that result
 Ignores the possibility that a particular outcome may be sufficient but not necessary for another

Thank you so much for your time. I really waste time here and get boggled down and would love any clarity/advice that you are willing to share. Thank you again and I hope you and your families are staying safe during this time.

[KelseyWoods]

Hi Foti!

In reality, the Mistaken Reversal and the Mistaken Negation are the same basic logical flaw. Consider this example:

Original Statement: A B

Mistaken Reversal: B A
Mistaken Negation: A B

Look at the relationship between the Mistaken Reversal and the Mistaken Negation--what do you notice? They're contrapositives of each other! Contrapositives are logical equivalents of each other. So the Mistaken Reversal and the Mistaken Negation are basically the same flaw. Since they're logical equivalents, the LSAT can't give you a description of the Mistaken Reversal and the Mistaken Negation in the same question and have one of them be the correct answer. Both of them could be incorrect. Or you could have two answer choices describing different types of conditional relationships.

Most of the time, if you have a Mistaken Reversal or a Mistaken Negation, you are just looking for an answer choice that includes terminology that refers to conditional reasoning. Usually that means terms like "sufficient," "necessary," or their synonyms like "enough" and "required." But the LSAT has wised up a bit to this trick so sometimes they try to describe a conditional flaw without those specific terms. Look at the example you gave: "Treats the failure to satisfy a condition that brings about a particular outcome as if satisfying that condition is the only way to realize that outcome." Here, we don't have the terms "sufficient" or "necessary." But we do have the term "only," which we know is a necessary indicator term. So this answer choice is describing a conditional flaw in which the author is treating a condition as a necessary condition even though it is not necessary.

Because LSAT authors are getting a little trickier with how they describe conditional flaws, you might find a couple of answer choices that describe conditional reasoning (but not typically the Mistaken Reversal and the Mistaken Negation because, again, those are logical equivalents). So it can be useful to unpack these answer choices to figure out what they mean.

First, I'm going to reorganize your list a bit. Confusing a necessary condition for a sufficient condition usually describes a Mistaken Reversal. Confusing a sufficient condition for a necessary condition usually describes a Mistaken Negation. So let's just break it into 2 categories:

Confuses a necessary condition for a sufficient condition (Usually a Mistaken Reversal)

• From the assertion that something is necessary to a given goal, the argument concludes that that thing is sufficient for its achievement
• Mistakes something that is necessary for a particular outcome for something that is merely sufficient for the outcome
• Treats a characteristic known to be true of one class of things as if that characteristic were unique to that class
• The argument confuses a necessary condition for species distinction with a sufficient condition for species distinction

Confuses a sufficient condition for a necessary condition (Usually a Mistaken Negation)

• Confuses a sufficient condition with a required condition
• Treats a sufficient condition for the airport's being built as a necessary condition
• Confuses a result with a condition that is required to bring about that result
• The author assumes that a condition that ensures a given result is required for that result
• Ignores the possibility that a particular outcome may be sufficient but not necessary for another
• Taking the absence of an occurrence as evidence that a necessary condition for that occurrence did not take place
• Treats the failure to satisfy a condition that brings about a particular outcome as if satisfying that condition is the only way to realize that outcome
• Mistakes being sufficient to achieve a particular outcome for being required to achieve it

Again, there's no logical difference between Mistaken Reversal and Mistaken Negation. Even these two categories are not functionally different--isn't confusing a necessary condition with a sufficient condition basically the same thing as confusing a sufficient condition with a necessary? But they do reflect slightly different ways that the LSAT might describe the flaw in an answer choice.

Let's look at an example argument:

"To go to law school, you must take the LSAT. Sally did not go to law school, so she must not have taken the LSAT."

If we diagram this argument, we find that it is a Mistaken Negation:
Law School LSAT
Sally: Law School LSAT

But what is a Mistaken Negation exactly? From the conditional rule, we know that going to law school is sufficient for taking the LSAT, but the author concluded that because Sally did not go to law school, she must not have taken the LSAT. Why did the author draw that conclusion? Because the author assumed that going to law school was necessary for taking the LSAT. We know from the contrapositive that if you don't have the necessary, you don't have the sufficient. Here, the author treated "Law School" as a necessary condition and "LSAT" as the sufficient condition, because he concluded that if you don't have "Law School," then you don't have "LSAT."

The LSAT authors might describe that flaw with an answer choice that looks like this:
"Confuses a sufficient condition with a required condition"

Let's de-abstract that answer choice: The author confuses a sufficient condition ("Law School") with a required condition because the author thinks that not satisfying that condition (not going to law school) is enough to prove that Sally did not take the LSAT.

Let's look at one more example:

"To go to law school, you must take the LSAT. Sally took the LSAT, so she must have gone to law school."

If we diagram this argument, we find that it is a Mistaken Reversal:
Law School LSAT
Sally: LSAT Law School

But what is a Mistaken Reversal exactly? From the conditional rule, we know that going to law school is sufficient for taking the LSAT, but the author concluded that because Sally took the LSAT, she must have gone to law school. Why did the author draw that conclusion? Because the author assumed that taking the LSAT was sufficient for going to law school. As in the Mistaken Negation example, the author treated "Law School" as a necessary condition and "LSAT" as the sufficient condition, because he concluded that if you have "LSAT," then you have "Law School."

The LSAT authors might describe that flaw with an answer choice that looks like this:
"Mistakes something that is necessary for a particular outcome for something that is merely sufficient for the outcome"

Let's de-abstract that answer choice: The author mistakes something that is necessary ("LSAT") for a particular outcome ("Law School") for something that is merely sufficient for that outcome because the author thinks that satisfying that condition ("LSAT") is enough to prove that Sally went to law school.

Look back at some previous Flaw questions you've seen involving conditional reasoning and try to de-abstract the answer choice by plugging in the specific conditions being referred to so that it becomes clearer as to what that answer choice is describing.

Hope this helps!

Best,
Kelsey

[Foti]

Kelsey, I just want to say thank you!! You really went above and beyond in your explanations. You were so thorough and detailed and it helped me more than you can probably understand! THANK YOU!

I have a few more questions. If you aren't busy and have some time I would love your feedback on them. They are on entirely different LR topics, however. I hope that's not asking for too much.

Nesting Conditionals
These conditional statements tend to get me a little confused and I end up spending too much time on them. Is there an easier way to break these down? I know there is a post on the forum that already breaks this down and I have referred to it quite a few times. Unfortunately, I'm still taking too long to answer these questions. Maybe a different approach/explanation will help. Also, is there by any chance a list of examples from past LSAT dealing with nesting conditionals that I can refer to for practice?

Double/Triple Negatives
Another area I tend to spend a lot of time on and where I tend to get questions wrong are questions dealing with multiple negatives. Is there an easy way to decode prose that has double/triple negatives? Again, is there a list of past LSAT questions where I can put these skills into practice?

Indirect Evidence Vs. Direct Evidence
In method of reasoning questions I have seen LSAT refer to evidence that can be direct and evidence that can be indirect. I understand that direct evidence is completely on topic. Im assuming the majority of evidence will be direct? What constitutes exactly as indirect evidence, then? I read somewhere that all examples are indirect evidence? Is that true? Is this something that occurs often?

Lastly, what exactly does it mean to "qualify an assertion" or "qualification" in general?
I understand that a qualification on the LSAT is more likely to refer to a clarification of a statement, especially placing a limitation on a statement. What exactly does it mean by placing a limitation on the statement, however? I want to make sure I understand the concept beyond just the definition.

Thank you again, I know this covers a wide range of questions. Whatever advice you are willing to give would really help. Thank you and I hope you are staying healthy and safe!

[Jeremy Press]

Hi Foti,

Thanks for your questions!

Nested Conditionals

The most important thing I can tell you about nested conditionals is that, while students often understandably feel a lot of anxiety about them, they're a relatively infrequently occurring phenomenon on the test. Nested conditionals do not appear on every exam. And when they appear, they tend only to appear on one or two of the logical reasoning questions out of the 50 (or 51) on the test. So try not to let them cause you too much anxiety!

When it comes to nested conditionals, the devil is very often in the details, meaning the form of the particular statement in question. And sometimes it's better to come up with a common-sense translation of the sentence in question rather than to try to force it into a conditional diagram. There are some really great thoughts on that holistic/translation-focused approach here: lsat/viewtopic.php?t=7733.

From a form/diagramming perspective, there are some general things that can be said about certain forms of nested conditional, which you can find in these two threads in particular (at least one of which I think you're referring to in your post!):
1. lsat/viewtopic.php?f=7&t=7992.
2. lsat/viewtopic.php?t=28532.

Notice in that second thread that Paul refers to a handy rule for one very specific form of nested conditional: "If A, then B, unless C." Such a statement can automatically be "translated" as: A B or C. You have to be careful, though, because if the form of the nested conditional changes (e.g., if the statement reads "If not B, then not A, unless C), then you'll have to change your way of applying that handy rule. This thread goes into detail on that change and what handling it requires: lsat/viewtopic.php?f=569&t=3528. The takeaway from this form and diagramming discussion is that it's unlikely anyone can give you one simple "trick" that can be universalized for every nested conditional. Focus on meaning and translation, if all else fails.

Unfortunately, we don't have a handy list of all questions utilizing nested conditionals. In addition to those linked above, I know of one good question with one right off the top of my head: it's December 2006 (PT 51), LR1, question 17. Interestingly, the place where they seem to appear most often is Principle questions (especially Must Be True—Principle questions), so check those questions first for more practice!

If you run into a specific question utilizing nested conditionals that you'd like help with, do let us know on that question's thread, because we'd love to work through it with you!

Double/Triple Negatives

The simple rule of thumb here is that two negatives, set side-by-side in a sentence and applicable to one single concept, cancel out to make the expression positive. So when I say an event is "not unlikely" to occur, I'm just saying it's likely to occur. Focus on the simple application of that rule, and if you have a more complex form you'd like us to address, definitely let us know on that particular question!

For these, I think we run into the opposite problem we had with nested conditionals. While nested conditionals don't appear frequently enough to warrant a comprehensive list, there are far too many stimuli and answer choices with multiple negatives to come up with a comprehensive list. To practice these in a focused way, my recommendation would be to take a section or two of logical reasoning (preferably older sections, so you're not burning recent PT material), and go actively looking for sentences with multiple negative piled up in them. For each one, break it down to the simplest translation possible. That way, you're both training yourself to recognize the problem every time it occurs, and to solve the problem in a way that is both accurate and understandable to you.

Indirect vs. Direct Evidence

Indirect evidence (also referred to as "circumstantial evidence") is evidence of something related to the matter at issue, from which an inference (whether strong or weak) can be drawn about the matter at issue. Let's say I'm trying to determine who ate the cookies in my cookie jar. Eating the cookies is the "matter at issue." Direct evidence would be: I see the dog eating the cookies with my own eyes (or my kids see the dog eating the cookies with their own eyes), or I have video of the dog eating the cookies. Indirect evidence would be: a trail of crumbs leading from the cookie jar to the dog's bed; dirty paw prints on the counter next to the cookie jar; the smashed cookie jar laying on the floor next to one of the dog's toys. As a purely practical matter, indirect evidence is actually much more common than direct evidence. Now I haven't done an empirical analysis of all evidence appearing in LR or RC questions/passages, but my very strong suspicion is that much more of the evidence you'd see there falls into the indirect than the direct category. I'm always hesitant to make universal claims (and I'd want to see specifically what you have in mind before I pronounce a judgment), but my guess is that most of the "examples" you see used as premises in arguments would constitute indirect evidence of the matter at issue. I can't off the top of my head think of a time where that specific distinction has been one I've needed to use on the LSAT, but I'm happy to talk about it more if you have a question where it's employed in mind!

Qualified Assertions

When it comes to qualifiers on the LSAT, the "limits" on assertions that we're most commonly concerned with are limits on the certainty of the statement being made (terms like "likely," "probably," "possibly," "usually," etc.); and limits on the quantity of the thing under discussion (terms like "most," "some," "many," etc.). But also keep an eye on "scope" qualifiers that limit the breadth of the category under discussion ("friendly dogs" versus "dogs").

I hope this helps!

Jeremy

[Foti]

Thank you, Jeremy. That makes perfect sense.

[Admin note: This student had follow-up questions on a similar topic that for clarity were moved here: https://forum.powerscore.com/lsat/viewt ... 12&t=32037]

[bearcats123]

Hi,
I had some general questions regarding the Flaw in the Reasoning question type. When looking for an answer, can you look for the weakness in the flaw, since flaw and weaken questions are similar? And can that help you identify the flaw if you cannot see what the flaw is for a question? Also will flaw answer choices sometimes be written like weaken answer choices? I know that weaken questions answer choices are more concrete and flaw in the reasoning answer choices are more abstract and will not bring in new information, but was unsure if there were any special cases where the test makers will do so and can bring in new information still.
Thank you!

[Rachael Wilkenfeld]

Hi bearcats123,

You won't see a weaken answer choice in a flaw question (or vice versa) because even though they both ask about where an argument goes wrong, they ask it in different ways. Weaken questions ask you to exploit the problem in the argument--to find a fact that would make the argument even worse. Flaw questions ask you to describe the problem in the argument. You aren't adding anything, just describing what is already on the page.

Let's think about a fairly common example of a terrible argument:

Studies have shown that it is impossible to eliminate the risk of car accidents on highways. Therefore, any spending on safety measures would be wasted, since the risk will remain.

That's a pretty common sort of argument, and completely flawed.

A weaken answer choice will give you facts that make it worse. For example, a study showing that minor spending on lighting decreases accidents 75%. That would weaken the argument by showing that the money wouldn't be wasted.

A flaw in the reasoning answer choice needs to describe why it's a bad argument. For example here, an answer choice could say that the author mistakenly concludes that because you can't eliminate a risk, you can't decrease the risk. A flaw answer choice is abstract and descriptive. A weaken answer choice is usually more concrete, and factual.

Noting where a weakness is in an argument is a great step in either a flaw in the reasoning question or a weaken question. The difference is where you go from there. You won't see new information in a flaw question because that wouldn't be a description of the argument.

Hope that helps!
Rachael