LSAT Explanation PT 39, S4, Q17: Ecologist: Forest fires, the vast majority
LSAT Question Stem
The conclusion drawn above follows logically if which one of the following is assumed?
Logical Reasoning Question Type
This is a Sufficient Assumption question.
Correct Answer
The correct answer to this question is B.
LSAT Question Complete Explanation
Let's first break down the argument in the passage:
Premise: Forest fires, mostly started by lightning, are natural and necessary for many forests to flourish.
Premise: Forest fires have various benefits, such as facilitating seed pod opening, preventing insect overabundance, and promoting forest diversity.
Conclusion: Human attempts to prevent or control forest fires are ill-advised and shortsighted; forest fires should be left alone to burn out naturally.
The question type is Sufficient Assumption, which means we're looking for an assumption that, if true, would guarantee the conclusion logically follows from the premises.
Now, let's evaluate each answer choice:
a) Human intervention in natural processes tends to reduce the biological diversity of ecosystems.
- This answer choice is tempting, but it doesn't guarantee the conclusion. It's a general statement about human intervention and doesn't specifically address forest fires or their prevention/control. It's also not strong enough to ensure the conclusion follows from the premises.
b) Protection of forests and their ecosystems is the only legitimate reason for attempting to prevent or control forest fires.
- This answer choice connects the premises and conclusion. If the only legitimate reason for preventing or controlling forest fires is to protect forests and their ecosystems, and we know that forest fires are necessary and beneficial for forests, then it logically follows that human attempts to prevent or control forest fires are ill-advised and shortsighted. This answer choice is correct.
c) Forest fires begun by careless campers should be the target of human fire control efforts.
- This answer choice is irrelevant to the argument. It doesn't address the benefits of forest fires or the conclusion that human attempts to prevent or control forest fires are ill-advised and shortsighted.
d) Humans tend to view forests as well as other ecosystems as instruments for the satisfaction of human needs.
- This answer choice doesn't help in establishing the conclusion. It's a statement about human views, but it doesn't address the benefits of forest fires or the reasons for not preventing or controlling them.
e) If the health of an ecosystem is threatened by insects or other predators, human beings should not intervene to block that threat.
- This answer choice is also irrelevant. It doesn't address the benefits of forest fires or the conclusion that human attempts to prevent or control forest fires are ill-advised and shortsighted. It focuses on a different aspect of ecosystem health.
In conclusion, answer choice B is the correct answer because it connects the premises and conclusion, ensuring that the conclusion follows logically from the premises.