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Sufficient assumptions | Worked example

Watch a demonstration of one way to approach a sufficient assumption question.

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  • blobby green style avatar for user mike.sabbagh
    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.
    (27 votes)
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  • blobby green style avatar for user A A
    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.
    (13 votes)
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  • blobby green style avatar for user Kai Burley
    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.
    (12 votes)
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  • blobby green style avatar for user raghav.sehgal2512
    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)
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  • marcimus pink style avatar for user aaryaprep
    what's the difference between a "necessary assumption" and a "sufficient assumption" ?
    (2 votes)
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  • boggle green style avatar for user jopang
    Is D a backwards choice?
    (2 votes)
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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.