Intensional negative adjectives alleged, artificial, fake, false, former, and toy are unusual adjectives that depending on context may or may not be restricting functions. A formal theory of their semantics, pragmatics, and context that uniformly accounts for their complex mathematical and computational characteristics and captures some peculiarities of individual adjectives is presented. Such adjectives are formalized as new concept builders, negation-like functions that operate on the values of intensional properties of the concepts denoted by their arguments and yield new concepts whose intensional properties have values consistent with the negation of the old values. Understanding these new concepts involves semantics, pragmatics and context-dependency of natural language. It is argued that intensional negative adjectives can be viewed as a special-purpose, weaker, context-dependent negation in natural language. The theory explains and predicts many inferences licensed by expressions involving such adjectives. Implementation of sample examples demonstrates its computational feasibility. Computation of context-dependent interpretation is discussed. The theory allows one to enhance a knowledge representation system with similar concept building, negation-like, context-dependent functions, the availability of which appears to be a distinct characteristic of natural languages.
