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Course: LSAT > Unit 1
Lesson 8: Logical Reasoning – Worked examples- Identify the conclusion | Worked example
- Identify an entailment | Worked example
- Strongly supported inferences | Worked example
- Working with disputes | Worked example
- Identify the technique | Worked example
- Identify the role | Worked example
- Identify the principle | Worked example
- Match the structure | Worked example
- Match principles | Worked example
- Identify a flaw | Worked example
- Match flaws | Worked example
- Necessary assumptions | Worked example
- Sufficient assumptions | Worked example
- Strengthen | Worked example
- Weaken | Worked example
- Helpful to know | Worked example
- Explain | Worked example
- Resolve a conflict | Worked example
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Sufficient assumptions | Worked example
Watch a demonstration of one way to approach a sufficient assumption question.
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- Can this get rescaled? Again there's a problem where all the answer choices aren't visible until the narrator scrolls down during the video.(26 votes)
- Question Type: Assumption
This question asks us to find a sufficient assumption, meaning one that, if true, will be enough to make the argument true. To tackle this question, we first find the core:
Premise #1: Anyone who believes in democracy has a high regard for the wisdom of the masses.
Premise #2: Griley believes that any artwork that is popular is unlikely to be good.
Conclusion: Griley does not believe in democracy.
Second, we find the assumption. Where is the mismatch between the premises and the conclusion? The only thing we know about Griley is that he thinks that any popular artwork is unlikely to be good. The only think we know about believing in democracy is that anyone who does so also has a high regard for the wisdom of the masses. Since the conclusion links Griley to not believing in democracy, it must be assuming that since he thinks popular artwork is unlikely to be good, he does not have a high regard for the wisdom of the masses, and therefore can’t possibly be someone who believes in democracy. Let’s look at the answer choices.
(A) This does not connect us back to our conclusion"”it has no mention of believing in democracy. It also does not link our premises together.
(B) Bingo! This links the premises together, which allows us to draw the conclusion. This is correct.
(C) We know that Griley is an elitist, so this is not helpful.
(D) This is the reverse of what we need.
(E) This doesn’t incorporate what we know about Griley, so it can’t help us link to the conclusion.(12 votes) - ANSWERS
(A) Anyone who believes that an artwork is unlikely to be good if it is popular is an elitist.
(B) Anyone who believes that if an artwork is popular it is unlikely to be good does not have a high regard for the wisdom of the masses.
(C) If Griley is not an elitist, then he has a high regard for the wisdom of the masses.
(D) Anyone who does not have a high regard for the wisdom of the masses is an elitist who believes that if an artwork it popular it is unlikely to be good.
(E) Unless Griley believes in democracy, Griley does not have a high regard for the wisdom of the masses.(5 votes) - This is a great question. How do we solve it fast? Diagramming helps in visualization but it does seem to take a lot of time.(3 votes)
- what's the difference between a "necessary assumption" and a "sufficient assumption" ?(2 votes)
- Is D a backwards choice?(2 votes)
Video transcript
- Anyone who believes in
democracy has a high regard for the wisdom of the
masses. Griley, however, is an elitist who
believes that any artwork that is popular is unlikely to be good. Thus, Griley does not
believe in democracy. The conclusion follows logically if which one of the following is assumed? Before I even look at
this, let's just try to deconstruct what the
author is trying to say because it does seem to make
a pretty big logical leap. Even if you accept what they're saying, this first statement, "Anyone
who believe in democracy has a high regard for
the wisdom of masses." They're saying, anyone
who believes in democracy, they're going to be a subset
of the people who have a high regard for the wisdom of masses. Let's say these are the folks
who believe in democracy. Believes in democracy. Let's say that circle is all of the people who believe in democracy. They're saying, "Anyone
who believes in democracy has a high regard for the
wisdom of the masses." Anyone who believes in democracy has a high regard for
the wisdom of masses. That means that all of these people have to have a high regard
for the wisdom of the masses. They're not saying that
everyone with a high regard for the wisdom of the masses
believes in democracy, so maybe the people with
the high regard for the wisdom of masses is a superset. High regard for mass wisdom. Anyone who believes in
democracy will also be in the set of people who have
a high regard for mass wisdom. Then they go to talk about Griley. Griley, however, is an elitist
who believes that any artwork that is popular is unlikely to be good. They're making this
statement about Griley, and they're saying that's he's an elitist. First of all, they're
just calling him a name, but then they say, "Who
believes that any artwork that is popular," so popular art... If he sees, or she, I don't
know if Griley's a he or she, but Griley, if they see popular art, then they think it unlikely to be good. Unlikely good. Obviously, these are all
things that someone else is saying is true about Griley. But even if you accept all this, they then make this
conclusion or this statement, "Thus Griley does not
believe in democracy," which feels like a bit of a jump. Griley does not believe in democracy. Something about this red
statement about Griley, somehow in this author's
mind it definitively puts Griley either, definitely
not in this circle, one who does not believe in democracy. Either in this one, where
Griley maybe has a high regard for mass wisdom but does
not believe in democracy, or is even sitting out
here, someone who does not have a high regard for mass wisdom. Then they're definitely not
going to believe in democracy. Somehow they're trying to
connect someone who thinks that if art is popular it's unlikely good, to sitting in one of these places where you wouldn't believe in democracy. Let's see if any of these key assumptions could help us there. One way to imagine is
test if this was part of the original statement,
whether it would make a little bit more logical sense. Let's see, Choice A. "Anyone who believes that an artwork is unlikely to be good if it is popular is an elitist." Well, no, this would just
justify the name-calling, why they're calling Griley an elitist. But it doesn't back up this
connection where if someone believes that something is
popular it's unlikely to be good, that that is somehow connecting to someone who does not believe in democracy. This is just justifying
calling someone an elitist, so I'd rule that one out. "Anyone who believes that
if an artwork is popular it is unlikely to be good," and they're saying that
that is true of Griley, that's this red part right over here, "does not have a high regard
for the wisdom of the masses." If this is assumed, if
Choice B here is assumed, then this statement about
Griley, which the passage does make, it puts Griley
on this dot right over here, outside of the set of people who have a high regard for the masses. If someone does not have a
high regard for mass wisdom, then they for sure are not
going to believe in democracy. This choice is actually
looking pretty good. If we added this to our original passage, the passage would make
little bit more sense. Let's try that out. "Anyone who believes in
democracy has a high regard for the wisdom of the masses. Griley, however, is an
elitist who believes that any artwork that is popular
is unlikely to be good. Anyone who believes that
if an artwork is popular is unlikely to be good
does not have a high regard for the wisdom of the masses." They don't have a high regard
for the wisdom of the masses, then they're definitely not
going to be in this orange set, which means that they're for sure not going to be in this blue
set that believes in democracy. I definitely like Choice
B. Let's see Choice C. "If Griley is not an
elitist, then he has a high regard for the wisdom of the masses." This is a little bit beside the point. Once again, like Choice A,
focusing on the word elitist. They're saying if he is not an elitist, then he has a high regard
for the wisdom of the masses. If you're not an elitist,
they're saying that you're at least going to be in this orange one, maybe you're in this blue one. But even if this was assumed,
you could still have elitists that have high regard
for the wisdom of masses, which might be a little bit
against the word elitist, but this doesn't really solidify the logical chain going on here. Choice D, "Anyone who does
not have a high regard for the wisdom of the masses," so that's anyone outside
of the orange here, "is an elitist who
believes that if an artwork is popular it is unlikely to be good." That's saying, if someone's out here, might be an elitist and they might have views on art like Griley, but it's not ruling out the possibility that Griley couldn't
necessarily be in here. I don't like this choice either. "Unless Griley believes in democracy, Griley does not have a high regard for the wisdom of masses." Unless Griley is here, unless
he believes in democracy, Griley does not have a high
regard for the wisdom of masses. Now, what's the problem with
this is you're still not making a connection
between this statement, this popular art that they're
claiming that Griley thinks that if something is popular
it's unlikely to be good, this one still doesn't make the connection between that and high regard
for the wisdom of masses or belief in democracy. It doesn't connect the two
parts of the statement, still, so I would rule that out. I feel really good about Choice B.