Abstract
Larry Horn is justifiably famous for his work on the semantics of the English conjunction or and both its relationship to the formal logic truth functions ∨ and @ (“inclusive” and “exclusive” disjunction respectively1) and its relationship to the ways people employ or in natural discourse. These interests have been present since his 1972 dissertation, where he argued for a “scalar implicature-based” account of many of these relationships as opposed to a presuppositional account. They have surfaced in his “Greek Grice” paper (Horn 1973) as well as in his Negation book (Horn 1989) and his recent “Border Wars” paper (Horn, forthcoming) where he defends the position that there are two types of implicatures at work here: Q- implicatures based on Grice’s first maxim of Quantity (“Say Enough”) and R-implicatures based on Grice’s second maxim of Quantity (“Don’t Say Too Much”). In a nutshell, the idea is that when a speaker employs a sentence with a disjunction, the meaning (that is, the semantic value) of the or is inclusive. With careful and judicious use of the Q- and R-implicatures, Larry’s theory allows the hearer (often) to infer that the speaker wanted to convey an exclusive disjunction.