Proceedings of the 1999 Conference of the Australian Linguistic Society 1 1. This is an abbreviated version of a similarly titled piece retrievable from http://www.arts.monash.edu.au/ling/lexicon_quantity.pdf. The Lexicon and Quantity Implicatures Keith Allan Monash University keith.allan@arts.monash.edu.au 1. Introduction The present paper is about the conversational implicatures (hereafter referred to simply as ‘implicatures’) that result from the two maxims of quantity identified by Grice 1975 and subsequently discussed by (amongst others) Atlas and Levinson 1981, Horn 1984, and Levinson 1995. The question I seek to resolve is whether Q[uantity] implicatures should be entered in the lexicon or whether they constitute encyclopedic information. Allan 1995, fc argues for a division of labour between the lexicon and the encyclopedia. The lexicon contains formal, morphosyntactic, and semantic specifications of listemes and the encyclopedia contains other kinds of information about listemes, e.g. their etymology, and information about their denotata. Conversational implicatures are pragmatic (Grice 1975, Gazdar 1979, Levinson 1983): they arise from the use of language in particular contexts. They differ from entailments in being defeasible. In other work (Allan 1999), Q1 implicatures, deriving from the first maxim of quantity, are included in lexical entries capture the default meaning (this is exemplified in §3). I shall argue here that what Jackendoff 1983, 1985, 1990 refers to as ‘preference conditions’ on lexical items are implicatures deriving from the second maxim of quantity augmented with the Atlas and Levinson principle of informativeness, a combination here referred to as Q2 — a quantity 2 implicature. Jackendoff incorporates preference conditions within his lexical entries. For instance, the lexical meaning of bird includes both an indefeasible part identifying the class of creatures (expressed in the lexicon as a truth statement), and a defeasible part “capable of flight” that identifies what is probably the case (in the absence of contrary evidence). Surveying as many examples of quantity implicature as space permits, I find that all Q implicatures based on a single lexical item are noted in the lexicon entry. Nonlexical implicatures arise from collocations of lexical items and can perhaps be located within the encyclopedia of which the lexicon is a part.