quadrilateral. trapezium, trapezoid, four sides, four angles, parallelogram. limited plane. logic. theoretical logic, science of thinking, art of applied logic, right thinking, treats of educational logic. laws of thought. star. Sirius, Arcturus, Vega. heavenly body, gives light and heat, twinkles. force. gravitation, molecular, { produces motion atomic. { changes motion { destroys motion. term. general, singular, word or group of words, non-connotative. definite idea. government. monarchy, aristocracy, body of people, democracy. established form of law, banded together for mutual protection. bird. crow, robin, pigeon. biped, feathered, winged. =5. OTHER FORMS OF EXPRESSION FOR EXTENSION AND INTENSION.= _Extension._ _Intension._ comprehension content extent intent breadth depth denotation connotation application implication Formerly the words extension and intension were applied to concepts while denotation and connotation were applied to terms representing the concepts, but now the words are interchangeable. Denotation, the noun, and denote, the verb, signify, etymologically, a _marking off_. To denote is to mark off or indicate the objects or classes of objects for which the term stands. Connotation, the noun, and connote, the verb, signify _to mark along with_. To connote is to mark along with the object, its attributes. The terms which should be remembered are extension } { intension or } and { or denotation } { connotation =6. LAW OF VARIATION IN EXTENSION AND INTENSION.= It has been noted that the intension of a term has reference to its qualities while extension considers its application to various objects. It may be wise to experiment with the extension and the intension of certain terms as types with a view of ascertaining how the two ideas are related to each other. For the sake of definiteness let us make use of the following scheme: I. _Intensional_ _Extensional_ (1) four sides } (2) parallel sides } common qualities of { (1) squares (3) equal sides } (4) right angles } (1) four sides } (2) parallel sides } common qualities of { (1) squares (3) equal sides } { (2) rhombs