What kind of generalizations can be made about the meaning of predicates? This paper compares two classes of predicates: summative predicates, which involve part-quantification, and integrative predicates, which do not. I start by sketching out a unified analysis of non-lexical aspects of their meaning, as motivated by the observation that all of these predicates are intuited as strong or weak in the same environments. However, summative predicates also have some formal properties that integrative predicates have not been described as having: they give rise to truth-value gaps and they can be 'non-maximal,' i.e., weak due to discourse factors. Since both of these properties arise post-lexically, a complete unification of the post-lexical meaning of summative and integrative predicates predicts that integrative predicates should display those properties too. I show that they do in fact display these properties, making a strong case for summative and integrative predicates having the same post-lexical semantic-pragmatic profile.