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Course: LSAT > Unit 1
Lesson 7: Logical Reasoning – Video lessons- Identify the conclusion | Video lesson
- Identify an entailment | Video lesson
- Strongly supported inferences | Video lesson
- Disputes | Video lesson
- Identify the technique | Video lesson
- Identify the role | Video lesson
- Identify the principle | Video lesson
- Match the structure | Video lesson
- Match principles | Video lesson
- Identify a flaw | Video lesson
- Match flaws | Video lesson
- Necessary assumptions | Video lesson
- Sufficient assumptions | Video lesson
- Strengthen | Video lesson
- Weaken | Video lesson
- Helpful to know | Video lesson
- Explain | Video lesson
- Resolve a conflict | Video lesson
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Match principles | Video lesson
Watch a demonstration of one way to approach a question that asks you to identify a statement that reflects a principle from the passage on the Logical Reasoning section of the LSAT.
Want to join the conversation?
- How does choice C match the principle? Why are we to assume that noxious fumes impair the judgement or ability of the workers? Could the fumes not simply be dangerous, and not necessarily impair the judgement of the worker?(4 votes)
- I think the instructor inferred that the thing affecting people (sleep deprivation, noxious fumes, etc.) was causing them not to realize how that thing was affecting them, but I don't believe this is a relationship we can infer. I'd state the principle more generally: "people are not always the best judges of how things are affecting them."(2 votes)
Video transcript
- [Instructor] To identify the question let's look at what it asks. Each of the following
illustrates the principle that the passage illustrates except. This is a match the principles question. The twist here is that it's
also an except question, which means that the four wrong
choices will be situations that share a principle with the passage and that the answer will be a situation that doesn't share a
principle with the passage. A principle is a sort of
general rule or generalization that governs a specific situation. One example of a common everyday principle that you might be familiar with is absence makes the heart grow fonder. So a situation that
conforms to that principle might be something like, Alexandra stayed angry at her
friends until she moved away and then she could only
remember the good things about their friendship. And then a situation
with a matching principle might be something like, David never got along with his brother until they lived in separate houses and didn't see each other very much then they became very close. See how we have two specific situations that contain the same principle. That's what we're looking for
when we match the principles. So pause your video now if you wanna try this question on your own otherwise we will move to the explanation. All right, let's read
this passage together and we'll pay attention
to what kind of principle might be at play. The passage reads, when
drivers are deprived of sleep there are definite behavioral changes, such as slower responses to stimuli and a reduced ability to concentrate, but people's self-awareness
of these changes is poor. Most drivers think they can tell when they are about to fall asleep, but they cannot. So here we have a situation. There's no argument,
there's no strong opinion, we just have some
information about drivers. It seems like a key point here is the discrepancy between what
driver's think is happening and what's really happening, in this specific instance of when drivers are deprived of sleep. So, drivers don't have enough sleep. And then they experience
behavioral changes but don't realize that they're
experiencing those changes. So they believe they'll be able to tell when they're about to fall asleep but they actually can't. And then the reason they can't is because they're sleep deprived. You see the issue here. They're so sleep deprived that they aren't equipped to tell if they're going to fall asleep. So if we were to phrase
a general statement that illustrates what's
being described here, it might be something like, sometimes people's physical
conditions cause them to not be able to make good decisions. It doesn't have to be precise. And in fact principles
are usually very general. Now remember that we're working
with an except question. That means that four of the choices will have the same principle and one won't. So let's evaluate each choice to see which one gives us a situation that doesn't illustrate
the principle we just saw. A, people who have been drinking
alcohol are not good judges of whether they are too drunk to drive. This illustrates the same principle we just saw in the passage. People have been drinking alcohol and that alcohol is
actually the precise reason they can't tell if they're
too drunk to drive. That's a match, so we can
eliminate this choice. B, elementary school students
who dislike arithmetic are not good judges of
whether multiplication tables should be included in
the school's curriculum. So this doesn't match the principle that we saw in the passage. There's no physical condition that's preventing the
students from being able to do something. It's just that these students are biased by their dislike of something. So they're too biased
to be considered good, reasonable judges of what should be in the school's curriculum. Since this situations principle doesn't match the passages principle and we're working with an except question, that means that this is our answer. We could select it and
move on, on test day if we feel confident, and
we would save ourselves a lot of trouble and time. Let's look at the remaining choices now in case you have questions on them. C, industrial workers who
have just been exposed to noxious fumes are not good judges of whether they should keep working. This is a beautiful match
for the passages situation. We have a physical condition, and that's being exposed to noxious fumes. And then that physical condition is exactly what's causing the workers to not be good judges of whether
they should keep working. The fumes are impairing the workers decision making abilities. D, people who have just donated blood and have become faint are not good judges of whether they are ready
to walk out of the facility. This choice also has a matching principle. The physical condition is of being faint from donating blood, and
their good decision is about whether they're ready to
walk out of the facility. And the physical
condition is stopping them from being able to make a good decision. E, people who are being treated for schizophrenia are not good judges of whether they should continue
their medical treatments. And this is our final matching principle. The physical condition is schizophrenia. And it's physically preventing people from being able to make a good decision about whether they should
continue their medical treatments. So to recap, for match
the principle questions it's a good idea to determine what principle governs the passage. And then you should be
able to identify the choice that illustrates that same principle. Or in this case, since we
had an except question, eliminate the choices that illustrate that same principle. The stronger your notion of a principle is the easier it usually
is to find the situation that has that same principle.