Four experiments and 2 corpus-based studies demonstrate that negation is a determinant factor affecting novel nonliteral utterance-interpretation by default. For a nonliteral utterance-interpretation to be favored by default, utterances should be potentially ambiguous between literal and nonliteral interpretations. They should therefore be (a) unfamiliar, (b) free of semantic anomaly or any kind of internal incongruity, and (c) unbiased by contextual information. Experiments 1–3 demonstrate that negative utterances, meeting these 3 conditions, were interpreted metaphorically (This is not a safe) or sarcastically (...) (Ambitious she is not) when presented in isolation and were therefore processed faster in contexts strongly biasing them toward their nonliteral than toward their (equally biased) literal interpretation. Experiment 4 reduces the possibility that it is structural markedness on its own that induces nonliteralness. Two corpus-based studies provide corroborating evidence, supporting the view of negation as an operator generating nonliteral interpretations by default. (shrink)