Logical Reasoning

PT131 · S3 · Q23 To predict that a device

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To predict that a device will be invented, one must develop a conception of the device that includes some details at least about how it will function and the consequences of its use.

Conclusion

The notion of preventing an invention is self-contradictory

Evidence

Predicting a device requires that you have a somewhat detailed conception of how the device will function / what its users will experience. Inventing something means coming up with a detailed conception. You can't predict what has already taken place.

Evaluation

The author is saying that I can't predict there will one day be a device invented called a "ketchup-gun", which would shoot ketchup onto burgers and hot-dogs using water gun technology, because when I came up with the detailed conception I just provided above, I basically just became the inventor of the "ketchup-gun".

And of course I can't predict that someone will one day invent the ketchup-gun, when I just invented it a second ago.

Goal

The author's conclusion is to show that a contradiction has occurred. He fleshes out the definitions of inventing and predicting to show that their definitions would contradict each other. Hard to predict answer wording, but we just need anything that matches the argument.

23.

Which one of the following most accurately describes the technique of reasoning employed by the argument?

  1. constructing a counterexample to a

    Out of Scope: "counterexample"

    Counterexamples are specific people/place/things/situations that go against a general rule. There is no general rule in this conversation, nor any specifically named people/place/thing/situation trying to go against that general rule.

    1% picked this

  2. Correct

    appealing to definitions to infer

    Why this is right

    Is the conclusion an inference about "an impossible kind of occurrence"? Sure, the conclusion is saying that "predicting an invention will never occur (it's self-contradictory)". Is the evidence an appeal to definitions? Sure. The first sentence defines what it means to "predict a device will be invented". The last claim defines what "inventing means".

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

    60% picked this

  3. countering a hypothesis by indicating

    Out of Scope: "hypothesis"

    There's no hypothesis anywhere here. A hypothesis is a claim that attempts to explain a given phenomenon. There's no phenomenon that has occurred nor any explanation for why it occurred. Even if we considered the principle / notion / proposition in the first sentence as a hypothesis, that first idea gets countered by showing that it's self-contradictory, which is not the same as showing that it has false implications. "False implications" would be like, "If X were true, then Y would follow. But since Y is false, X must be wrong." Y, in that example, was the false implication. That's not the same as showing that a claim is internally contradictory. To be self-contradictory, you are saying "there's no way both of these things could be simultaneously true", but that's dealing with the claim itself, not an implication of the claim.

    25% picked this

  4. pointing out how a problem

    Out of Scope: "scientific vs. conceptual"

    Nothing in this paragraph talks about a problem that is widely thought to be scientific.

    0% picked this

  5. attempting to show that predicting

    Opposite

    The author is saying the opposite of this in his final claim: you cannot predict something that has already taken place. The author thinks that predicting an event implies that the event has NOT yet taken place.

    13% picked this

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