Multiple propositions, contextual variability, and the semantics/pragmatics interface

A 'multiple-proposition (MP) phenomenon' is a putative counterexample to the widespread implicit assumption that a simple indicative sentence (relative to a context of utterance) semantically expresses at most one proposition. Several philosophers and linguists (including Stephen Neale and Chris Potts) have recently developed hypotheses concerning this notion. The guiding questions motivating this research are: (1) Is there an interesting and homogenous semantic category of MP phenomena? (2) If so, what is the import? Do MP theories have any relevance to important current questions in the study of language? I motivate an affirmative answer to (1), and then argue that MP theorizing is quite relevant to debates at the semantics/pragmatics interface.