|
Drawing an Affirmative Conclusion From a Negative Premise
Definition:
The conclusion of a standard form categorical syllogism is
affirmative, but at least one of the premises is negative.
Examples:
- All mice are animals, and some animals
are not dangerous, therefore some mice are
dangerous.
- No honest people steal, and all honest people
pay taxes, so some people who steal pay
pay taxes.
Proof:
Assume that the premises are true. Find an example
which allows the premises to be true but which
clearly contradicts the conclusion.
References:
26 May 1995
|