Must be TrueDiff: Medium
Logic Breakdown
Passage Summary: For a planet to have life, it needs a steady tilt, which is only possible if it has a large moon nearby to keep it stable; Earth has this, but Mars does not.
Reasoning: A planet requires a stable axis tilt to support life, and a stable tilt can only be maintained by the gravitational pull of a large, nearby moon.
Analysis: This stimulus establishes a chain of necessary conditions: Life requires a stable tilt, and a stable tilt requires a large moon. In formal logic terms, this is 'Life → Stable Tilt → Large Moon.' To find what 'Must be True,' we should look for a statement that follows this chain or its contrapositive, such as 'No Large Moon → No Life.' Be careful not to fall for a 'Mistaken Reversal,' such as assuming that any planet with a large moon must have life. The moon is a requirement, not a guarantee.
Reasoning: A planet requires a stable axis tilt to support life, and a stable tilt can only be maintained by the gravitational pull of a large, nearby moon.
Analysis: This stimulus establishes a chain of necessary conditions: Life requires a stable tilt, and a stable tilt requires a large moon. In formal logic terms, this is 'Life → Stable Tilt → Large Moon.' To find what 'Must be True,' we should look for a statement that follows this chain or its contrapositive, such as 'No Large Moon → No Life.' Be careful not to fall for a 'Mistaken Reversal,' such as assuming that any planet with a large moon must have life. The moon is a requirement, not a guarantee.
Passage Stimulus
Passage Redacted
Unlock Full Passage14.If the statements above are true, which one of the following must also be true on the basis of them?
Correct Answer
B
If Earth’s Moon left, the tilt could not be kept fairly stable (since it’s kept fairly stable only by the Moon), and without a stable, moderate tilt, the climate could not support life. This follows directly from the premises.
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