Temporal in-adverbials lead a double life. Under one guise, they specify the durations of events; under another, they specify the durations of stretches of time throughout which certain events do not take place. Each variety comes with its own seemingly idiosyncratic distributional restrictions. The distribution of the first class of expressions is restricted by the lexical aspect of VPs (Vendler, 1967; Dowty, 1979; Krifka, 1989). The distribution of the second class is restricted by the polarity of the sentences in which
they occur (Gajewski, 2005, 2007; Hoeksema, 2006; Iatridou & Zeijlstra, 2017, 2021). I argue for a unified semantic analysis of both classes which derives from one semantic principle their eclectic distribution: it must be possible for temporal in-adverbials to
provide a maximally informative measure.