Logical Reasoning Flashcards
Where will the reasoning flaws exist?
between the support and the conclusion. That is the only flaw the LSAT is concerned with - the flaw in the relationship between the conclusion and the support used.
Why doesn’t the support justify the point?
if we take the support to be true…
is it enough, by itself, to absolutely PROVE the main point?
three questions you ask yourself for every logical reasoning question.
What’s the point?
how is it supported?
what’s wrong with that?
piece does not equal puzzle
when the author falsely overvalues one consideration and the expense of others.
three subsets of piece doesn’t equal puzzle
overvalues a trait, overvalues an opinion, overvalues a sample set
overvalues a trait
putting too much emphasis on one particular characteristic or “clue” to reach a conclusion. If it is not enough to guarantee the outcome, the argument is flawed.
primary driver
determining whether or not a certain characteristic is a “primary drive is SUBJECTIVE
we are being asked to be OBJECTIVE
they are testing your ability to look for absolute proof
REMEMBER- every characteristic is NOT enough to prove the authors point.
overvalues an opinion
the truth is never the truth because someone says it is. the truth is the truth because it’s the truth.
one’s opinion does not guarantee anything
an opinion cannot prove that an argument is false the same as it cannot prove an argument is true.
no opinion can prove something that is subjective.
overvalues a sample set
arguments are flawed when they reach a general consensus based on evidence from a limited portion of whatever group or system they are discussing
on the LSAT, we do not question…
our job is not to question whether the reasoning given is in fact true
extrapolation
the action of estimating or concluding something by assuming that existing trends will continue or current method will remain acceptable.
placing too much significance on one characteristic, one opinion, or an unrepresentative sample set.
faulty transferring
transferring information or ideas from one situation to another in some faulty way.
author falsely equates subject matter
author falsely equates characteristics
author falsely equates relationships
falsely equates subject matter
it’s best to focus on the differences in subject matter between the support and conclusions.
falsely equates characteristics
LSAT will use assumed, but not actual opposites.
the author is mistakenly equating not being something with being some sort of opposite of that thing.
You don’t have to be tall to be short - you could be somewhere in the middle.
falsely equates relationships
The LSAT there can be a very strong connection between the subject mentioned in the support and the subjects mentioned in the conclusion. However, the relationship can be altered in some way.
most of x is y and most of y is x is NOT VALID
enough, but not necessary
one way to falsely equate characteristics is to assume that one way to do something is the only way to do something, or mistaking one way for the only way.
“mistaking sufficient for necessary”
the author uses evidence that one element or characteristic is enough to reach the outcome to conclude that the element or characteristic MUST BE involved with the outcome.
which one of the following, if assumed, allows the argument’s conclusion to be properly drawn?
what answer makes the conclusion one hundred percent guaranteed based on the reasoning given.
Context issues
the subjects and characteristics mentioned in the premises will be an almost exact match for those that are in the conclusion, but the argument will still be flawed.
the argument could fail to take account of its context - the situation might be different, but the author assumes it has stayed consistent.
Reasoning issues
the author jumps to a conclusion or equates things that shouldn’t necessarily be equated through changes in subject matter, characteristic, or relationship.
correlation and causation
no amount of correlation can even prove a causal relationship
ask yourself: would that be enough information to be CERTAIN
evidence of correlation, or lack thereof, can strengthen or weaken a claim of causation, but it could never, ever prove a claim of causation.
of the following, which one most accurately expresses the main point of the argument?
what do we think is the conclusion within the argument, then find the answer that best represents that understanding.
The part about ____ figures in the argument in which one of the following ways?
decide the role played by the part in question then find the answer that best represents that understanding.
A component’s role is defined by how it relates to the main point.
“the argument’s reasoning is questionable because the argument…”
what is wrong with the argument?
think about the argument critically before moving on to the answers
“which one of the following, if true, most seriously weakens the argument?”
figure out what is wrong with the argument then select the answer that exposes that flaw.
Tempting wrong answers will relate to the conclusion or the support, but not the problem that exists between them.
“each of the following, if true, would strengthen the argument EXCEPT”
figure out what’s wrong with the argument then eliminate answers that help fix that issue.
the right or may or may not weaken the argument - it might actually have no direct impact on the argument.
“which one of the following is an assumption on which the argument depends on?”
start by figuring out what is wrong with the argument.
the key word here is “depends” that does not mean that the right answer needs to be important in addressing the argument flaw. It simply means that the answer is something that needs to be true in order for the argument to work.
“Each of the following describes a flaw in the argument EXCEPT”
get a clear sense of the problems in the relationship between the support and the conclusion then eliminate the four answers you think best describe the problems
“which of the following arguments contains a flaw in reasoning that is similar to one in the argument above?”
figure out what is wrong with the argument.
work to eliminate answers that either reach. very different type of conclusion use different types of support, or seem to have different problems. confirm the correct answer by matching conclusions, support, and reasoning issues.
if our job is to be subjective
Evaluate the argument (the reasons given to justify a point made)
the reasons will never justify the point made
understanding why its not justified is the most important factor
if our job is to be objective
it is absolutely critical to NOT judge
the wrong answers will prey on our subjectivity
conclusion in a logical reasoning stimuli
the conclusion is going to be an opinion of some sort
if it were fact, it would not need justification
the conclusion will be something that is debatable and needs to be justified
you should see that other elements in the argument are meant to compel you to think a certain statement is true
the statement being supported is the conclusion
Flaw questions stems
“the reasoning in the argument is most vulnerable to criticism on the ground that it…”
“The reasoning in the argument is flawed in that…”
“which of the following is an error in the reasoning”
steps for flaw and basic assumption questions
step one: read the question stem. once we read the question stem we know that our job s to find the argument and find out what’s wrong with the argument
step two: identify the conclusion of the argument in your first read. If the conclusion is unclear, do not move on.
step three: find the support for the main point. The support is usually only one or two reasons.
Step four: figure out what’s wrong. have a conceptual grasp on the flaw. know what’s wrong instead of knowing the wording of what’s wrong.
Step five: get rid of answers.
Step six: confirm the right answer. go word for word, and pay attention to modifiers that may create a disconnect between the answer choice and the stimulus
what is most important to remember for flaw questions
directly related to your understanding of the argument as can be.
reasoning flaws are not contained in the conclusion and they are not contained in the support.
must figure out what is wrong with using that particular support with that particular conclusion.
more than any other question, you need to make sure you understand what is wrong with the argument before moving on to the answers.
the right answer will typically hit the issue right on the head.
possible wrong answers in flaw questions
- misrepresents the relationship between the support and main point in some way
- the answer is unrelated to reasoning
- the answer is unrelated to the conclusion
- the answer is unrelated to the stimulus
un-abstract argument for
“ifers from the fact that a certain factor is sufficient for a result that the absence of that factor is sufficient for the opposite result”
since eating ____ makes one healthy, not eating ___ makes one unhealthy.
un-abstract version of
“takes for granted that, if a condition coincided with the emergence of a certain phenomenon, it must have been causally responsible for that phenomenon”
I got sick right after I ate that taco. The taco must have made me sick.
un-abstract version of
“fails to address adequately the possibility that even if a condition is sufficient to produce that effect, it might not be necessary”
I got fit by working out everyday. If you want to get fit, you must work out everyday.
un-abstract version of
“mistakes a merely relative for one that is absolute”
since Jessica has more money than Tara, Jessica must be rich
un-abstract version of
“presents as a premise a claim that one would accept as true only if one already accept the truth of the conclusion”
Of course what _ is saying is true. _ would not be saying it otherwise.
un-abstract version of
“bases a generalization on a sample that is likely to be unrepresentative”
Since the managers at the company state that their employees are thoroughly grateful to be working under them, this must indeed be the case
un-abstract version of
“interprets an assertion that certain conditions are necessary as asserting that those conditions are sufficient”
In order to become a pop star, one needs to be able to dance well. since I can dance well, I will become a pop star.
basic assumption question stems
basic assumption questions are flaw questions in disguise.
they simply ask us to state the problem in an argument in terms on an assumption the author has made
“what does the argument assume”
“the author assumes that…”
steps for match the flaw and match the reasoning questions
step one: understand your job. very commonly these flaws are the 1+1=3 variety.
step two: find the main point. the key is to not fragment from your primary focus. the conclusion is particularly important in match questions. if the conclusion is unclear, do not move on.
step three: in general, match the flaw questions tend to have less secondary information. most commonly, everything other than the conclusion will be support.
step four: figure out what’s wrong
step five: get rid of answers. focus on one part of the stimulus at a time.
step six: confirm the answer. make sure the conclusions match. make sure there’s the same support. make sure there are no star words that change the meaning of the answers in some way. CHECK MODIFIERS
wrong answers in match the flaw/reasoning will be
- clearly reach different conclusions
- use different support
- different flaw
Sufficient assumption question stem
identify an answer that would completely fix the reasoning issue in an argument
“the conclusion follows logically if which of the following is assumed?”
“which of the following, if assumed, allows the conclusion to be properly drawn?”
steps to sufficient assumption/supporting principle
1- understand the job: they have the word “assumption”, that assumption is typically phrased in terms of a condition (if assumed, and other types of assumption questions almost never have the word if) and they include some sense that the argument would, with the assumption, be made logical or valid
2- find the point. get a sense of the overall flow of the reasoning. pay attention to whether your dealing with a typical support-conclusion argument or a series of supporting premises. if it’s a series of supporting premises, look for the flaw in the reasoning has to do with some sort of missing link in the change.
3- find the support. either traditional support-conclusion or chain link.
4- find out what’s wrong. its important to remember that the arguments for Sufficient assumption questions will have one clearly definable hole or flaw. Keep the hole in the argument and how it might be fixed separate: the gap may be filled in a way you do not expect
5- get rid of answers. attractive wrong choices match the argument in terms of subject matter and attractive wrong answers can help strengthen the argument, sometimes a lot, but that’s DIFFERENT from making the argument valid.
6- confirm your answer. if you place the answer between the support and the conclusion, it should make the conclusion one hundred percent justifiable.
3 different types of assumption questions
BASIC assumption
SUFFICIENT assumption
REQUIRED assumption
mistaking sufficient for necessary
one way for the only way
the author uses evidence that one element of characteristic is enough to reach the outcome to conclude that THAT element or characteristic MUST be involved in the outcome
necessary, but not enough
some of the hardest arguments to find fault wither those that give us characteristics that are needed to reach the conclusion but are not, by themselves, enough to definitely prove the argument is correct.
a trait that is enough to justify the conclusion is sufficient
supporting principle question stem
the author’s reasoning most closely conforms to which one of the following principles?
which one of the following principles, if valid, most helps to justify the economist’s reasoning?
things to remember for sufficient assumption
- have a very clear sense of the flaw
- bridge the gap between the reasoning given and the conclusion reached
- stay on task
the answers need to COMPLETELY FIX THE PROBLEM WITH THE ARGUMENT.
keep in mind the right answers could go above and beyond what is needed.
what is a “principle” on the LSAT?
a principle is just a rule that is generalized
things to remember for supporting principle questions
- have a very clear sense of the flaw
- bridge the gap between the reasoning given and the conclusion reached
- the flaws and arguments will be less absolute and abstract than Sufficient Assumption
- the right answers may not always have the same sense of closure
- stay on task
conform to principle question stems and things to remember
“the reasoning above most closely conforms to which of the following principles?”
“which one of the following propositions is most precisely exemplified by the situation presented above?”
same steps as sufficient assumption and supporting principle, but the gaps will be written less as flaws and more as opinions.
possible wrong answers for sufficient assumption/supporting principle/conform to principle questions
- doesn’t fill the hole
- unrelated to the reasoning
- unrelated to the conclusion
- unrelated to stimulus
things to remember about required assumption
what NEEDS to be true
these questions ask that we figure out the gap in reasoning, then find one answer that needs to be true if that gap is going to be filled.
a big key to Required Assumption questions is to stick to a specific and narrow understanding of “required”
we are not being asked to strengthen the argument, or even fix the argument.
steps to required assumption
1- understand your job. the questions almost always have the word assumption and almost never the word if. they must have some other word that indicates - such as required, rely or depend
2- find the point. your job is to identify the flaw and find the one answer that needs to be true if the support is ever going to actually prove the point.
3- find the support. you want to isolate the critical components- the point and support- and carefully evaluate the relationship.
4- figure out what’s wrong.
5- get rid of answers. in general, you cannot anticipate the answer for a required assumption question. DON’T ELIMINATE AN ANSWER BECAUSE IT DOES NOT MATCH WHAT YOU WERE EXPECTING.
The most tempting wrong answers are ones that seem to support the argument in some way or perhaps even completely fix the argument. while something may fix it, it is not needed or required for the argument to be fixed. there is a difference between helpful and required, and we need to stay focused on required.
6- confirm the right answers. keep in mind the difference between required and helpful. if one answer needs to be true for the argument to work but hardly helps it, and another answers completely fixes all issues, but not in a. way they need to be fixed, the first answer will be correct. check with the negation test
wrong answers for required assumption questions
- perhaps helpful, but not required
- unrelated to reasoning
- unrelated to conclusion
- unrelated to stimulus
negation test for required assumption questions
if you negate an answer choice and the negation does not hurt the argument, the answer was not something that was necessary to the argument.
definition of “required” in required assumption stems
required DOES NOT equal important
the right answer to a required assumption question might be very important to the argument, or it may be secondary, but nonetheless it needs to be true in order for the argument to work.
a required assumption need not fix the argument or even get close to fixing it, it is simply something that needs to be true if the argument is going to work.
required assumption question stems
asking us to identify an assumption that needs to be true for the conclusion to be true.
which of the following is an assumption required by the argument?
the argument relies on which one of the following assumptions?
which one of the following is an assumption on which the argument depends?
strengthen and weaken question stems
which of the following, if true, most strengthens the argument?
which of the following, if true, most weakens the argument?
which of the following, if true, most calls into question the author’s reasoning?
things to remember about strengthen and weaken questions
right answers need not make the argument perfect, and generally will not.
some of the most tempting wrong answers for s/w are the ones that s/w the author’s point, but not in a way that impacts how he made the point originally (the reasoning)
wrong answers for strengthen weaken questions
- plays a different role relative to the argument
- related to the conclusion, but not the reasoning
- unrelated to the conclusion
- unrelated to the stimulus
steps for s/w questions
1- understand your job.
2- find the point. a s/w question will require you to understand the flaw in the argument and then identify the one answer that matches the task.
3- find the support. these questions will always have the statement “if true.” we want to focus our energy on how that answer choice, if true, impacts the relationship between the support and conclusion
4- figure out what’s wrong. watch out for fluff.
5- get rid of wrong answers. look out for answer choices that strengthen or weaken the conclusion, but not in a way that seems to relate to the reasoning you originally considered. REMEMBER YOUR JOB IS TO STRENGTHEN OR WEAKEN THE AUTHORS ARGUMENT, NOT POINT.
6- confirm your chosen answer. THIS STEP IS PARTICULARLY IMPORTANT FOR STRENGTHEN WEAKEN QUESTIONS. you can avoid many costly mistakes by confirming that the answer you select plays the correct role and you can “fit” the answer in between the support and the conclusion.
