This paper investigates utterances with the structure A is not A, showing that they can be fully informative and are felicitously used and understood in discourse. Relying on the notions of metalinguistic and metarepresentational negation, we argue that the class of utterances A is not A is heterogeneous and differs in regard to the lower-order representation under the scope of the negative operator. Specifically, we distinguish negated tautologies and copular contradictions. The understanding of negated tautologies involves identifying the corresponding affirmative deep tautology (Bulhof & Gimbel, 2001) and rejecting the assumptions derived from it. The interpretation of copular contradictions is based on distinguishing each of the occurrences of the repeated constituent as describing (a) one single referent with different properties; (b) two different referents satisfying the same description in different evaluation worlds; (c) two different referents, with different properties, which are accessed by means of the same linguistic expression.