8. SUMMARY.
1. Connotative terms are used in a two-fold sense: first, to denote objects; second, to imply qualities.
2. A term is used in extension when it is employed with reference to the objects for which the term stands. A term is used in intension when it is employed with reference to the qualities for which the term stands.
3. The answer to either of the following questions will lead one to use any term in extension: First, what are the kinds? or second, to what objects may the term be applied?
The answer to either of the following questions will lead to the use of any term in intension: First, what does it mean? or second, what are the qualities?
4. To illustrate extension and intension it is best to use the class-names in every day speech.
5. The word denotation is commonly used for extension and connotation for intension.
6. “As the intension of a term is increased its extension is decreased and vice versa,” is a statement of the Law of Variation in the extension and intension of terms.
6a. The law of variation applies only to a series of terms representing notions of the same class or family, the wordsbeing arranged in a species-genus order. The increase and decrease of the extension and intension of a series is not proportional.
6b. The law of variation is best explained by using two triangles, one super-imposed upon the other vertex to base and base to vertex.