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Celarent Syllogism
A valid syllogism with negative conclusion: No A are B, All C are A, therefore No C are B.
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A valid syllogism with negative conclusion: No A are B, All C are A, therefore No C are B.
Celarent is the second of the 'perfect' syllogisms in Aristotle's first figure. It combines a universal negative (E) premise with a universal affirmative (A) premise to derive a universal negative conclusion. The name 'Celarent' uses vowels E-A-E to indicate the proposition types: universal negative, universal affirmative, universal negative.
No M are P, All S are M ⊢ No S are P
- No reptiles are mammals. All snakes are reptiles. Therefore, no snakes are mammals.
- No even numbers are odd. All multiples of 4 are even. Therefore, no multiples of 4 are odd.
- No fish can breathe air. All salmon are fish. Therefore, no salmon can breathe air.
How to recognize it
- One premise uses 'No' (universal negative) and one uses 'All' (universal affirmative)
- The conclusion is always 'No' (universal negative)
- The middle term connects the chain through negation
Common mistakes
- Confusing the direction: 'No A are B' is not the same as 'No B are A' in context
- Missing that both terms in the conclusion inherit the negative relationship
Step-by-step walkthrough
No reptiles are mammals. All snakes are reptiles. What can we conclude?
- Identify the negative premise: 'No reptiles are mammals'
- Identify the affirmative premise: 'All snakes are reptiles'
- Since snakes are reptiles, and reptiles are excluded from mammals...
- Conclude with universal negative: No snakes are mammals
Answer: No snakes are mammals
Practice guidance
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