Logical Reasoning

PT151 · S4 · Q21 Evolution does not always optimize

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Evolution does not always optimize survival of an organism.

Conclusion

Evolution does not always optimize survival of an organism.

Evidence

Male moose evolved giant antlers as a way to determine the dominant males, for whom the giant antlers provide a survival benefit.

But those giant antlers make it harder to escape predators, since the antlers can easily get tangled in trees.

All male moose would be better off with antlers half the current size (for the sake of escaping predators), assuming they could preserve whatever relative size/status advantage they have over their peers.

Evaluate

On Method questions, the correct answer usually pulls from this list of concepts:

presents Analogy

rules out alternate possibilities

provides (counter)example of general claim

discusses implications of logic

calls out dubious assumption

raises overlooked consideration / distinction

defines a term

suggests alternate explanation

This one seemed to start with a very general claim about evolution and then illustrate it by discussing the case of the male moose.

Goal

Let's look for something like "providing an example to illustrate a generalization".

21.

Which one of the following is a technique of reasoning used in the argument?

  1. citing an example to cast

    Out of Scope: competing argument

    We love the first three words! But, not so much the rest. There was no competing argument. That author isn't fighting anyone else's position. The author is citing an example to support a generalization.

    18% picked this

  2. employing an analogy in order

    Out of Scope: analogy

    The example of the male moose is meant to support the generalization in the first sentence. We could imagine an unspoken generalization, "Evolution always optimizes the survival of an organism", and yes the argument does employ a counterexample to dispute that generalization. But it doesn't employ an analogy. Disputing with analogy Jane is not going to love the Performing Arts school that accepted her, even though it's her dream school. After all, Jose got into his top choice law school and ended up hating it. Disputing with counterexample Getting into one's dream school does not always make one happy. After all, Jose got into his top choice law school and ended up hating it. Notice that we're using Jose identically in both cases. What makes the first case an analogy, and the second case a counterexample is the difference between the initial claims. Analogy = 2 specific stories that both embody the same (unspoken) general idea Example = 1 specific story that embodies an explicitly stated general idea

    6% picked this

  3. Correct

    challenging a general claim by

    Why this is right

    We have to look at the conclusion in the first sentence and think, "Yes, he's challenging a general claim, because it would be a general claim to say evolution always optimizes survival of an organism, and he's challenge that." Is the evidence a counterexample, a case in which "evolution happened, but it didn't optimize the survival of an organism?" Sure the moose is a case where evolution caused the giant antlers and the giant antlers actually impede the moose's survival somewhat.

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

    62% picked this

  4. disputing the relevance of an

    Out of Scope: opposing view / dispute

    The author is presenting what she thinks is a very relevant example (or counterexample, technically). There isn't an opposing view named that the author is fighting. While the main conclusion (first sentence) is arguing against a general claim, that claim has been attributed to anyone, so we can't call it anyone's view. That invisible view has not presented a supposed example, and the author does not attack the relevance of that supposed example.

    7% picked this

  5. undermining a claim by showing

    Too Strong: self-contradictory

    The idea of contradictory (aka, inconsistent / incompatible) is wrong over 90% of the time we see it. Self-contradictions are incredibly rare. The author is undermining the claim "evolution always optimizes survival of an organism". If we were showing that this claim were self-contradictory, we'd be saying "That's crazy talk! After all, evolution literally means "to lessen the survival value of an organism", so how could it possibly optimize survival?"

    8% picked this

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