Aspect and Aktionsart: Fighting or Cooperating?

It is widely accepted that semanti(: ttle-ories should, as far as possible, be com-positional. The claim that a dmory is (:omt)ositional, however, lacks bite if lexical and pre-lexical items are allowed to mean dilrerent things ill difl'erent contexts. The aim of the current paper is to show how to deal with a well-known t)henolnenon by relying on (:ombinato-rim effects to infer difforent consequences from the same items in difl'erent contexts without altering the contributions that these items make individually.