Logical Reasoning

PT115 · S4 · Q17 Ecologist: Forest fires, the vast

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Ecologist: Forest fires, the vast majority of which are started by lightning, are not only a natural phenomenon to which all forest ecosystems are well adapted, but are required for many forests to flourish.

Conclusion (should)

Forest fires should be left alone and allowed to burn themselves out naturally.

Evidence

Forest fires are a natural phenomenon that is required for many forests to flourish (they facilitate seed pods, limit insects, and promote diversity).

Evaluate

The final sentence is the Conclusion, indicated by "In view of this (evidence)". It's technically two claims joined by a semicolon. We might wonder whether LSAC wants us to prove , or whether they want us to prove .

In either case, we know that the evidence launchpad we have includes supporting buzz phrases such as: - required for forests to flourish - facilitate seeds dispersal - limit insects - promote diversity

I see the last three in that list as sub-components of the first one. The bottom three seem like reasons why forest fires are required for many forests to flourish.

Goal

We want an answer to give us a rule that takes us from one of the Evidence launchpads and gets us to one of the Conclusion landing zones.

If .... Then .... req'd for forests to flourish ill-advised and or shortsighted to helps w/ seed dispersal prevent/control or or limits insects should be left or alone to burn out promotes diversity

17.

The conclusion drawn above follows logically if which one of the following is assumed?

  1. Human intervention in natural processes

    Wishy-Washy (tends to) Unrelated to Goal

    On Sufficient Assumption, if you had to guess, you would never guess any answer that wasn't 100% black and white, because almost all correct answers are. Words like "generally, tends to, typically, usually, etc." don't provide the certainty we need for a correct answer. Also, this answer doesn't have either of the conclusion phrases we're looking for: "ill-advised / shortsighted" or "should be left alone to burn out naturally"

    35% picked this

  2. Correct

    Protection of forests and their

    Why this is right

    "The only legitimate reason" is getting at the normative language we're looking for, to prove a conclusion about "should we / shouldn't we". If you don't have a legitimate reason, then you shouldn't do it. This answer says, if your attempt to not a legitimate prevent or control ? reason to prevent forest fires isn't or control forest to protect forests fire or their ecosystems From the Evidence, do we know whether our attempts to prevent/control forest fires are about trying to protect forests and their ecosystems? We do. We know it's not about that, because we were told "all forest ecosystems are well adapted to forest fires". We were also told that many forests couldn't flourish without forest fires, and then we heard about all the good things that forest fires do. So forests certainly ain't asking us to stop forest fires. Since they're all well-adapted to fires and benefit from fires, our attempts to prevent/control forest fires must be for some other reason, and thus they are not legitimate (thus, we should not be attempting to prevent or control them). The correspondence between the correct answer language and the conclusion is a little bit more of a stretch than we usually see on Sufficient Assumption, but the strength of language is unequivocal (the only) and the meaning of "you have no legitimate reason to do X" is pretty close to "you should not do X".

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

    51% picked this

  3. Forest fires begun by careless

    Weakens

    The author is categorically saying "forest fires should be left alone", not "forest fires should generally be left alone, except those caused by careless campers". This answer actually goes against the author's conclusion.

    2% picked this

  4. Humans tend to view forests

    Unrelated to Goal Wishy-Washy (tend to)

    We don't really care about how humans tend to view forests. We need a rule with normative force that allows us to definitely say "humans should never be attempting to prevent or control fires".

    1% picked this

  5. If the health of an

    Bad Trigger Match

    This has the conclusion language we'd like, "Humans should not do X". Does the trigger apply to "forest fires"? We obviously know that forest fires are not insects and forest fires are not predators, but are forest fires something that threatens the health of an ecosystem? We were actually told the opposite. We were told that all forests are well-adapted to forest fires and that many forests are threatened if they don't have forest fires (they need the fires to flourish). Since we were never told that forest fires threaten the health of an ecosystem (in fact, we were mostly told the opposite), there's nothing we can do with this rule to connect it to forest fires.

    11% picked this

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