Is there a principled difference between entailments in natural language that are valid solely in virtue of their form or structure and those that are not? This paper advances an affirmative answer to this question, one that takes as its starting point Gareth Evans’s suggestion that semantic theory aims to carve reality at the joints by uncovering the semantic natural kinds of the language. I sketch an Evans-inspired account of semantic kinds and show how it supports a principled account of (...) structural entailment. I illustrate the account by application to a case study involving the entailment properties of adverbs; this involves developing a novel proposal about the semantics for adverbs like ‘quickly’ and ‘slowly’. In the course of the discussion I explore some implications of the account for the place of model-theoretic tools in natural language semantics. (shrink)

Proof-theoretic models of grammar are based on the view that an explicit characterization of a language comes in the form of the recursive enumeration of strings in that language. That recur-sive enumeration is carried out by a procedure which strongly generates a set of structural de-scriptions Σ and weakly generates a set of strings S; a grammar is thus a function that pairs an element of Σ with elements of S. Structural descriptions are obtained by means of Context-Free phrase structure (...) rules or via recursive combinatorics and structure is assumed to be uniform: binary branching trees all the way down. In this work we will analyse natural language constructions for which such a rigid conception of phrase structure is descriptively inadequate, and pro-pose a solution for the problem of phrase structure grammars assigning too much or too little structure to natural language strings: we propose that the grammar can oscillate between levels of computational complexity in local domains, which correspond to elementary trees in a lexicalised Tree Adjoining Grammar. (shrink)