Logical Reasoning

PT15 · S3 · Q13 Reptiles are air-breathing vertebrates

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Reptiles are air-breathing vertebrates with completely ossified skeletons; so alligators must be air-breathing vertebrates with completely ossified skeletons.

Conclusion (so)

Alligators must be air-breathing vertebrates with completely ossified skeletons.

Evidence

Reptiles are air-breathing vertebrates with completely ossified skeletons.

Evaluate

This is a lovably short argument and 90% of it is just one long, repeating symbol ("air-breathing V's with ossified S's").

The evidence establishes that a certain group (reptiles) has a certain trait (air-breathing vertebrates w/ completely ossified skeletons).

Then the conclusion picks a member of that group (alligators are a type of reptile) and concludes that this member must also have that trait.

Goal

Look for something like this: Premise: Group X has trait A. Conclusion: Member of Group X has trait A.

13.

In terms of its logical features, the argument above most resembles which one of the following?

  1. Correct

    Green plants take in carbon

    Why this is right

    We can match this up with the original: Prem: Group X has trait A. Green plants take in CO2, release oxygen. (Reptiles are air-breathing V's with ossified S) Conc: Member of Group X has trait A. Green plants take in CO2, release oxygen. (Alligators are air-breathing V's with ossified S)

    Skill tested: Parallel · how this choice captures the argument's function is the move to repeat next time.

    79% picked this

  2. Some red butterflies are poisonous

    Bad Premise Match

    The premise here is not telling us about a Group that all has a certain trait. The premise in the original was about all reptiles, of which alligators are one member. The premise in the correct answer is about all green plants, of which green grass is one member. The premise in this answer is about some red butterflies, and the "particular red butterfly" in the conclusion may or may not be a member of that group.

    1% picked this

  3. Knowledge about the empirical world

    Weak Premise Match

    It's tough to say that the premise here could be construed as telling us about a Group that all has a certain trait. The premise is saying, "It's possible to gain knowledge about the empirical world from a book. It can be done." That's different from saying, "all books provide knowledge about the empirical world", which is what we would need it to say for the Conclusion to work the way it did in the original argument. In other words, the fixed version of this answer is: "Books provide knowledge about the empirical world; so Virginia Woolf's book A Room of One's Own must provide knowledge about the empirical world".

    8% picked this

  4. Dierdre has seen every film

    Weaker Evidence / Conclusion Match

    This argument could actually match the original, if we express it a little differently and treat "Dierdre has seen it" as the trait. Prem: Group X has trait A. Fassbinder-movies have all been seen by Dierdre. Conc: Member of Group X has trait A. Fassbinder's Ali: Fear Eats the Soul has been seen by Dierdre. If we didn't have a better option, then we could conceivably stretch this answer to work, but because we have to do manipulation to get it to look parallel to the original, this isn't as close a match as was the correct answer, which required no manipulation to look parallel.

    12% picked this

  5. Skiers run a high risk

    Bad Conclusion Match

    The fact that this conclusion is not certain of itself ("likely" vs. "must be"), will be enough to disqualify this from consideration.

    1% picked this

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