Human language is unique among the communication systems of the natural world. The vocabulary of human language is unique in being both culturally-transmitted and symbolic. In this paper I present an investigation into the factors involved in the evolution of such vocabulary systems. I investigate both the cultural evolution of vocabulary systems and the biological evolution of learning rules for vocabulary acquisition.

In reports filed from several fronts in the semantics/pragmatics border wars, I seek to bolster the loyalist (neo-)Gricean forces against various recent revisionist sorties, including (but not limited to) the relevance-theoretic view on which the maxims (or more specifically their sole surviving descendant, the principle of relevance) inform truth-conditional content through the determination of “explicatures”, Levinson’s defense of implicatures serving as input to logical form, recent arguments by Mira Ariel for a semantic treatment of the upper bound (‘not all’) for propositions of the form Most F are G, and Chierchia’s proposal to reanalyze implicatures as part of compositional semantics. I argue for drawing the semantics/pragmatics boundary in a relatively traditional way, maintaining a constrained characterization of what is said, while adopting a variant of Kent Bach’s position on “impliciture” and supporting the Gricean conception of implicature as an aspect of speaker meaning, as opposed to its reconstruction in terms of default inference or utterance interpretation. I survey current controversies concerning the meaning and acquisition of disjunction and other scalar operators, the relation of subcontrariety and its implications for lexicalization, the nature of polarity licensing, and the innateness controversy. In each case, I seek to emphasize the signiÞcance of the generalizations that a (neo-)classical pragmatic approach enables us to capture. For some time, David Kaplan (cf. Kaplan 1978:223) has taken to harking nostalgically back to

The Mutual Exclusivity (ME) constraint – a preference for mapping one word to one object – has been shown to be a powerful aid to children learning new words. We ask whether cross-situational language learning, in which word meanings are learned through computation of word-object co-occurrences across a series of highly ambiguous trials, is subject to the ME constraint. Our results show that participants can break the constraint to learn one-to-two word-referent mappings both when the referents are separated across time and when they are interleaved. This demonstrates the robustness of crosssituational statistical learning. We then use participants ’ ratings of their knowledge after individual trials to shed light on the underlying learning mechanism. Our results suggest that the ME constraint may be applied at multiple points along learning – within a single trial, across trials, and at test – which may explain one of its residual test effects found in the traditional language literature.

Recent research on children’s inferencing has found that although adults typically adopt the pragmatic interpretation of some (implying not all), 5- to 9-year-olds often prefer the semantic interpretation of the quantifier (meaning possibly all). Do these failures reflect a breakdown of pragmatic competence or the metalinguistic demands of prior tasks? In 3 experiments, the authors used the visual-world eye-tracking paradigm to elicit an implicit measure of adults ’ and children’s abilities to generate scalar implicatures. Although adults ’ eye-movements indicated that adults had interpreted some with the pragmatic inference, children’s looks suggested that children persistently interpreted some as compatible with all (Experiment 1). Nevertheless, both adults and children were able to quickly reject competitors that were inconsistent with the semantics of some; this confirmed the sensitivity of the paradigm (Experiment 2). Finally, adults, but not children, successfully distinguished between situations that violated the scalar implicature and those that did not (Experiment 3). These data demonstrate that children interpret quantifiers on the basis of their semantic content and fail to generate scalar implicatures during online language comprehension.

Developmental semantics and pragmatics 0 Semantic meaning and pragmatic interpretation in five-year olds: Evidence from real time spoken language comprehension