Logical Reasoning

PT10 · S1 · Q22 No one knows what purposes

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No one knows what purposes, if any, dreams serve, although there are a number of hypotheses.

Hypothesis

Dreams are produced when the brain is erasing "parasitic connections" (accidental associations between ideas) that build up during the day and would otherwise clog up our memories.

For an animal that doesn't dream to have an effective memory, it would need a big brain in order to accommodate all the accumulating clutter.

Goal

Let's find an answer that aligns with any of the hypothesis's ideas.

Maybe data points showing the brain is slightly smaller after dreaming than it was before.

Maybe an animal that doesn't dream and doesn't have a big brain, and thus has an ineffective memory.

22.

The parasitic-connection hypothesis, if true, most strongly supports which one of the following?

  1. The animals with the smallest

    Too Strong: smallest / most

    This glosses over the nuances of this hypothesis. It's not predicting that "the more you sleep, you smaller your brain is". It's predicting that "the more you dream, the more your brain can clear out clutter so that your memory works better".

    5% picked this

  2. Immediately after a person awakens

    Too Strong: virtually no accidentals

    The hypothesis believes that dreams help to erase parasitic connections (i.e. accidental associations between ideas). It never says that dreams clear out almost all accidental associations. This just gets too quantitatively precise and extreme for us to derive it.

    10% picked this

  3. Correct

    When a mammal that would

    Why this is right

    The hypothesis is that dreams clear out some of the parasitic connections that would otherwise clog up our memories. This answer is doing to ol' Flip the Causal Difference-Maker. It stands to reason then if we don't dream, we won't get rid of the parasitic connections, and so our memories will be clogged up. The reason they specify "a mammal that would normally dream" is because the passage allows for the idea that some animals might evolve a different "solution" for this problem (rather than dreaming, these animals just have larger brains so that they can handle that extra clutter). So the answer is specifying that we're not talking about that sort of creature. We're talking about a mammal that does regularly dream.

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

    71% picked this

  4. Insofar as a person’s description

    Out of Scope

    Out of Scope: description of a dream Nothing in the passage or the hypothesis is talking about how people describe their dreams. We're only talking about the biological purpose served by dreaming.

    8% picked this

  5. All animals other than the

    Too Strong: all animals

    We have pretty good support for the idea that "all mammals other than the spiny anteater dream", but we can't say that the spiny anteater is the only animal on Earth that doesn't dream.

    5% picked this

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