A formal logical fallacy, which is committed when a categorical syllogism employs two universal premises (”all”) to arrive at a particular (“some”) conclusion. In a valid categorical syllogism, if the two premises are universal, then the conclusion must be universal, as well.
Examples:
- All forest creatures live in the woods. All leprechauns are forest creatures. Therefore, some leprechauns live in the woods.
Synonyms: existential instantiation