Saving monotonic modals with ranked ordering sources

Abstract

In this paper, I argue that Jackson (1985)’s Professor Procrastinate (PrP) problem is not inconsistent with a quantificational semantics for deontic modals. In particular, the apparent inability to infer ought(?) from ought(?) is because the modals in the two sentences are interpreted with respect to two distinct ordering sources, and these contexts differ in the relative ranking that they assign to different priorities. I show how formalisms for modeling contextual priority rankings—particularly the ordered merging operation (Katz et al., 2012) and ranked ordering sources (Reisinger, 2016)—account for the PrP problem and argue that ranked ordering sources better account for priority-sensitive modals in embedded contexts.