Abstract : Negative events have been used in analyses of various natural language phenomena such as negative perception reports and negative causation, but their conceptual and logical foundations remain ill-understood. We propose that linguistic negation denotes a function Neg, which sends any set of events P to a set Neg(P) that contains all events which preclude every event in P from being actual. An axiom ensures that any event in Neg(P) is actual if and only if no event in P is. This allows us to construe the events in Neg(P) as negative, "anti-P", events. We present a syntax-semantics interface that uses continuations to resolve scope mismatches between subject and verb phrase negation, and a fragment of English that accounts for the interaction of negation, the perception verb see, finite and nonfinite perception reports, and quantified subjects, as well as negative causation.