Logical Reasoning

PT140 · S3 · Q15 Amoebas, like human beings

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Amoebas, like human beings, generally withdraw from stimuli that cause them physical damage.

Conclusion (thus)

All microscopic organisms must also be capable of feeling pain.

Evidence

Amoebas, like human beings, generally withdraw from stimuli that cause them physical damage.

Humans do this because such stimuli cause them pain.

Evaluate

We could choose to take advantage of the repeating symbols (humans, pain, withdrawing from damaging stimuli) and turn this into algebra.

Premise 1: X's, like Y's, generally do A in response to B.

Premise 2: Y's do it because of reason Z.

Conclusion: All things like X must have some sensitivity to reason Z.

We can also focus on the type and strength of claims used. The premises should involve a comparison between two categories of things. There should be a second premise about one of those categories of things. The conclusion should be an all claim.

But we can also choose to respond conversationally. Why does this argument fail to convince us that "all microscopic organisms are capable of feeling pain"?

1. Microscopic organisms don't have a nervous system or a brain or, probably, any consciousness at all. How could they feel pain?

2. Why is the conclusion talking about all microscopic organisms? The evidence only talked about amoebas. This seems to be a Sampling flaw, because the author seems to be thinking that , of which amoebas are just one type.

Goal

The easiest thing to look for at a glance would be the relationship between the conclusion "All things in category X" and a premise, which needs to be about one specific type of X.

If an answer has that, we'll try to confirm that the argument uses a comparison structure, and argues,

15.

Which one of the following exhibits flawed reasoning most similar to that exhibited by the argument above?

  1. Correct

    Poets, like people under hypnosis,

    Why this is right

    The conclusion is about all artists and we have a premise about a type of artist, "poets". Is the evidence going off a comparison between poets and something else? Yes. It's saying, "Poets and hypnotized people are both X -- they both use language in weird ways". (just like "amoebas and humans both withdraw from damaging stimuli"). Does the rest of the argument say, "since hypnotized people are Y, then all artists are Y"? Yes, it says "Hypnotized people do it because of lowered inhibitions, therefore all artists do it because of lowered inhibitions." This matches up with "humans do it because of pain, therefore all microscopic organisms are doing it because of pain." This replicates both flaws of the original argument: 1. the author is assuming that because poets/hypnotized people are alike in one regard, they'll be alike in another. 2. the conclusion generalizes from 'poets' to a broader category that includes 'poets' (all artists).

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

    67% picked this

  2. Like nonprofit organizations, corporations usually

    Bad Conclusion Match

    This conclusion is not an "all" claim that's sure of itself, like the conclusion of the original argument. It's a "most" claim that's probably true. That's enough to ditch this answer on a first pass. The conclusion is about "most corporations", but there isn't a premise that's about one specific type of corporation.

    13% picked this

  3. Most professional athletes practice regularly

    Bad Conclusion/Evidence Match

    This conclusion is not a claim that's sure of itself, like the conclusion of the original argument. It's a probably claim. That's enough to discount this answer on a first pass. The conclusion is about "professional skaters", but there isn't a premise that's about one specific type of professional skater. In the original argument the premise (amoebas) was more specific than the conclusion (all microscopic organisms). In this argument the premise (pro athletes) is more general than the conclusion (pro skaters).

    5% picked this

  4. Predatory birds, like many predatory

    Bad Conclusion/Evidence Match

    This has identical problems to (C). The conclusion is not a claim that's sure of itself; it's a probably claim. In the original argument the premise (amoebas) was more specific than the conclusion (all microscopic organisms). In this argument the premise (predatory birds) is more general than the conclusion (hawks).

    5% picked this

  5. Hiking trails in British Columbia,

    Bad Evidence Match

    This conclusion looks promising, because it's an all claim that's sure of itself. But we don't have the Category vs. Category Member relationship between Conclusion and Premise that we had in the original argument. In the original argument the conclusion was a broad category (all microscopic organisms) and the premise was one member of that category (amoebas). In this argument the conclusion is a broad category (hikers), but there's a premise that's a specific type of hiker.

    10% picked this

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