Logical Reasoning

PT120 · S4 · Q10 Researcher: All defects in short-term

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Researcher: All defects in short-term memory are caused by a malfunction of a part of the brain called the hippocampus.

Conclusion (thus)

If a kid has a learning deficit, the hippocampus is messed up.

Evidence

Learning is the process of acquiring new info in long-term memory.

New information is held in short-term memory for a few secs, and then either moved into long-term or forgotten.

If there's a short-term memory defect, the hippocampus is messed up.

Evaluation

The evidence seems to prove that a messed up hippocampus could lead to a learning deficit, since we know that short-term memory is crucial to learning (by transferring info into long term memory, which is what we mean by 'learning') and we know that when the short-term memory is messed up, it's because of the hippocampus.

But just because the hippocampus could be involved in a causal story leading up to a learning deficit, it's not clear why the author thinks he can say that all learning deficits trace back to problems with the hippocampus.

Goal

This has the fuzzy vibe of Necessary vs. Sufficient, since the author has provided us info to give us a causal chain moving one way: bad hippo → bad short-term → no long term → can't learn

But he's trying to go the other way: can't learn → bad hippo

We need to point out this flaw or point out what it ignores: there could be other possible causes of learning deficits besides a bad hippocampus leading to messed up short term memory.

10.

The reasoning in the researcher's argument is most vulnerable to criticism on the grounds that this argument

  1. draws a general conclusion based

    Bad Evidence Match

    Does the author draw a general conclusion? Yes, "Whenever a child has a learning deficit ...". Is the author's evidence a limited sampling of learning deficits? No, it's a discussion about short term memory and the hippocampus.

    2% picked this

  2. Correct

    presumes, without giving justification, that

    Why this is right

    Conditionally, this answer looks like, "If learning deficit → bad short term memory" Does it feel fair to say the author's argument is making that move? Yes, since the conclusion says, "if learning deficit → bad hippocampus", and we know from the author's evidence that, "bad short term memory → bad hippocampus". If we combine the author's assumption with her evidence, we see where she derived her conclusion. "learning deficit → bad short → bad hippo" Pushing back against this assumption is the same as making our objection, "Couldn't there be other sources of a learning deficit besides this one short term memory / hippocampus story you're telling?"

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

    84% picked this

  3. presumes, without giving justification, that

    Backwards Logic

    The author said "defective short term → defective hippo" and this answer accuses him of thinking, "defective hippo → defective short term"

    10% picked this

  4. fails to quantify precisely the

    Never a Flaw

    This is a reasoning test, not a science or math test. We never need precise times, weights, measurements. We don't even need precise definitions of terms, as long as they given us some definition of terms.

    1% picked this

  5. takes for granted that learning

    Out of Scope: adults vs. kids

    The conclusion is just about kids. We don't care in analyzing this argument what's going on with adults.

    2% picked this

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