Affirmative conclusion from a negative premise
- Affirmative conclusion from a negative premise
Affirmative conclusion from a negative premise is a logical fallacy that is committed when a categorical syllogism has a positive conclusion, but one or two negative premises.
For example::"No fish are dogs, and no dogs can fly, therefore all fish can fly."
This could be illustrated mathematically as:If "A" ⊄ "B" and "B" ⊄ "C" then "A" ⊂ "C".
It is a fallacy because any valid forms of categorical syllogism that assert a negative premise must have a negative conclusion.
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