Share on Facebook Share on Twitter Email
Answers.com

Affirmative conclusion from a negative premise

 
Wikipedia: 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.

The only thing that can be properly inferred from these premises is that some things that are not fish cannot fly, provided that dogs exist.

This could be illustrated mathematically as

If AB and BC then AC.

It is a fallacy because any valid forms of categorical syllogism that assert a negative premise must have a negative conclusion.

References



Search unanswered questions...
Enter a question here...
Search: All sources Community Q&A Reference topics
 
 

 

Copyrights:

Wikipedia. This article is licensed under the Creative Commons Attribution/Share-Alike License. It uses material from the Wikipedia article "Affirmative conclusion from a negative premise" Read more