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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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Sufficient assumptions | Video lesson
Watch one way to approach a question that asks you to identify a sufficient assumption on the logical reasoning section of the LSAT.
Want to join the conversation?
- How can you distinguish between a Necessary Assumption and a Sufficient Assumption? What key words should we look for?(5 votes)
- How is the answer in this question different from a necessary assumption?(4 votes)
- would theses types of question strengthen ?(1 vote)
- Technically yes. Sufficient assumption questions are a type of strength. The difference is that SAQ makes the relationship between the support and conclusion a guarantee with no room to poke holes in the relationship vs a 'strengthen question' makes the relationship more robust but it doesn't necessarily always have to guarantee the conclusion. In order from least to most strengthening questions on the last, you have to strengthen questions, pseudo sufficient assumptions then sufficient assumptions. Hope this helps!(2 votes)
- it is not clear to me why this couldn't also be an example of a necessary assumption.(1 vote)
- I misunderstood the word "inappreciable." I thought it would mean too "large to appreciate" in this context, similar to how people say inconceivable. For that reason I answered C initially (I was incorrect of course, but I don't know how to improve my score with this information).(1 vote)
Video transcript
- [Instructor] To determine
what kind of question this is, let's jump below the passage
to the question itself. The conclusion of Morris's
argument follows logically if which one of the following is assumed? This idea of an assumption
guaranteeing a conclusion to follow from its evidence means that we are dealing with a
sufficient assumption question. The answer will be a claim that ensures a connection
from evidence to conclusion and the other four
choices, the wrong choices, will be claims that don't
allow the conclusion to follow from its support, either because they're not relevant or maybe they're a necessary assumption, but not a sufficient one,
some reason like that. Pause your video now if you'd like to try this question on your own, otherwise, let's move
on the the explanation. Okay, let's read the stimulus together. When reading for a sufficient assumption, concentrate on the main conclusion and main evidence of
each speaker's argument. A lot of the times, you'll be able to detect a gap between the
conclusion and evidence, and then the answer will close that gap. Okay, Morris says, "Computers, despite some
people's expectations, "will have an inappreciable
impact on education. "To be sure, computers are useful "for drills promoting memorization,
though only a small part "of education can be
accomplished through drills. "But machines cannot
help students with any "of the higher intellectual
functions we call understanding; "for that, human teachers
are indispensable." Okay, first, let's mark our conclusion. We don't have any clear
conclusion signal words that jump out at us right away, so let's decide what the
entire argument is meant to try to prove. Morris opens up by
predicting that computers, despite some people's expectations, will have an inappreciable
impact on education. So, we ask ourselves, does
the rest of the passage serve to support that idea? And the answer's yes. A good clue is also
that Morris is rebutting what some people expect to happen. That's a very common conclusion structure. And then the rest of the passage
explains Morris's thinking as to why computers won't really have a big impact on education. It's because even though
computers are useful for drills promoting memorization, machines can't help students with any of the higher intellectual
functions we call understanding, and there's our argument. In a nutshell, Morris is saying, computers can do some good things, but they won't have a big
impact on education because they can't help students with
higher intellectual functions. This last part of the passage here is sort of a parenthetical about teachers. It doesn't add anything
material to the argument, so we can consider it
background or context. Now, to find a gap in an argument, it can be extremely
helpful to look for an idea or concept that kind of
comes out of nowhere. So, look at our progression here. On the conclusion side,
we're talking about how computers can't have
a big impact on education. What's the star player
of the evidence, though? The spotlight of the evidence is how computers can't help students with higher intellectual functioning, so we need to bridge these two concepts. In other words, what is Morris assuming? Well, Morris is assuming that if something can't help students with higher
intellectual functioning, then that something can't have
a big impact on education. If we assumed this to be true, then Morris's argument would be ironclad. The evidence would flow directly to the conclusion via this assumption and that is exactly what a
sufficient assumption does. So, we have a super strong prediction and that's a great goal to have for sufficient assumption questions. If you have a really strong prediction, you are much less likely to
get lost in all the choices. You might be able to quickly scan and just find your match
on test day within seconds, and that would be ideal. For completion's sake, though, let's go through each
choice, one-by-one, in full. A, whatever memorization is
necessary can be accomplished as easily without computers as with them. This choice doesn't connect
the gap in the argument. The part of the argument dealing with memorization isn't even
part of the main argument. It's just a side note, like
a concession about one thing that computers are good for. We need to connect the ideas of higher intellectual functions and having an impact on education. B, requiring memorization
in appreciable amounts tends to thwart development of
higher intellectual functions in students. This is like A in that it focuses
on requiring memorization, but we don't care about memorization. We could seriously cut
that entire sentence about memorization from the passage and it wouldn't change the
argument's main structure, so this choice is irrelevant
and we can cut it. C, successful memorization
of relevant facts is a necessary precondition
for the development of higher intellectual
functions in students. Once again, I am so glad
we have a strong prediction because our prediction has
nothing to do with memorization and so far, three of
the choices have opened with memorization. It may be true that
memorization is necessary for development of higher
intellectual functions in students, but we're
still told in the passage that computers can't help students with higher intellectual functions. And if they can't help, they can't help, so choice C doesn't give us anything that ties the argument together. D, many students become familiar with computers before
encountering them at school. This choice doesn't do anything for us in terms of guaranteeing that the conclusion will
follow from its support. If many students are
familiar with computers before encountering them at school, but computers can't help students with higher intellectual functions, which is what we're told, then maybe computers can
have an impact on education and maybe they can't. Familiarity with computers
isn't relevant to this argument, we need to tie in higher
intellectual functions. E, having an appreciable
impact on education involves affecting the
higher intellectual functions of students. This is a match for our prediction. You might've been surprised
by the way it was worded. We said our prediction was
that if something can't help students with higher
intellectual functioning, then that something can't have
a big impact on education. Choice C is actually the
logically equivalent statement. If something does have a
big impact on education, then that something must involve affecting the higher intellectual
functions of students. That is a match, and just
in case you can't see it, logically equivalent
statements are like this. If I'm at the beach, then I
must have found my sunscreen is logically equivalent to,
if I didn't find my sunscreen, then I'm not at the beach. To test choice E, try adding it to the evidence from the passage and see if it leads to
the same conclusion. This choice tells us that
appreciable impact on education involves affecting higher
intellectual functions and then the support
from the passage told us that machines can't help students with higher intellectual functions. If we combine these two statements, what could we definitely conclude? Machines can't have an
appreciable impact on education and that is the conclusion
from the passage. That means that we have
found the assumption that guarantees the conclusion
to follow from its evidence. So, to recap, for sufficient
assumption questions, it's very, very helpful if
you can phrase the conclusion and the evidence simply
and accurately on test day. Then you can look for the gap between the evidence and the conclusion and make a prediction for
what connects the gap, and that connection is what ensures that the conclusion follows logically. If you wanna test the choice, you can add it to the passage evidence and ask yourself what the implication is when you add the choice to the evidence. If that implication matches
the passage's conclusion, then you have the answer. Watch out for choices that aren't relevant to the main argument. In this example, we saw
three choices that dealt with memorization and that
was part of the passage that didn't even contribute
to the main structure. So, it's really important to stay sharp with identifying your main
conclusion and the main evidence and look for the gap that
the answer will close.