Critical Reasoning – Implicit Assumptions Statement: “There is no reason to rule out the possibility of life on Mars. Therefore, exploration of that planet has to be undertaken.” Assumptions: I. There is life on Mars. II. Searching for life is a sufficient reason to undertake space exploration.
Verbal Reasoning
Statement and Assumption
Difficulty: Easy
Choose an option
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AOnly assumption I is implicit
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BOnly assumption II is implicit
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CEither I or II is implicit
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DNeither I nor II is implicit
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EBoth I and II are implicit
Answer
Correct Answer: Only assumption II is implicit
Explanation
Introduction / Context:The argument moves from “possible life” to “we should explore.” We must find the premise that allows this move without overstating claims about actual life on Mars.
Given Data / Assumptions:
- Premise: Possibility of life on Mars cannot be ruled out.
- Conclusion: Therefore, exploration must be undertaken.
- Assumption I: There is definitely life on Mars.
- Assumption II: The search for life (even as a possibility) is sufficient justification for exploration.
Concept / Approach:From “possible” to “do it,” the missing link is a value judgment: that the potential discovery (life) warrants the cost/effort of exploration. The conclusion does not require the fact of life, only the sufficiency of the goal.
Step-by-Step Solution:
I is not required; asserting existence would be stronger than the premise. The argument works with possibility, not certainty.II is required; without treating the search for life as sufficient reason, the conclusion to explore would not follow.Verification / Alternative check:
Negate II: if searching for life is not enough reason, then the conclusion to explore does not hold just from “possibility.”Why Other Options Are Wrong:
I-only/Both: Overstate the premise; certainty is not claimed.Either/Neither: Fail to supply the needed normative premise.Common Pitfalls:
Confusing possibility with actuality in assumption problems.Final Answer:Only assumption II is implicit