Why compositionality won't go away: Reflections on Horwich's 'deflationary' theory

Paul Horwich argues for a 'deflationary' account of compositionality, accor ding to which, '...the compositionality of meaning imposes no constraint at all on how the meaning properties of words are constituted'. We have arriv ed at a tentative diagnosis, which is that Horwich fails to enforce several distinctions that turn out to be crucial. For example, sometimes he puts h is main conclusion in the way we just quoted but sometimes, even on the fol lowing page, he puts it like this: 'understanding one of one's own complex expressions (non-idiomatically) is, by definition, nothing over and above u nderstanding its parts and knowing how they are combined'. We propose, in w hat follows, to consider how Horwich's deflationary account of compositiona lity fares if the distinction between theories of meaning and theories of u nderstanding is properly attended to. here's how we think it all turns out: --Horwich is right to claim that compositionality is neutral with respect to the metaphysics of understanding expressions when 'understanding' refers to a (merely) dispositional state; but not when it refers to an occurrent state. --Horwich is right strictu dictu to claim that compositionality is n eutral with respect to the character of lexical meanings, but only strictu dictu. Compositionality taken, together with other constraints that semanti c theories are required to satisfy, reduces the options in the theory of le xical meaning to a bare minimum. The first part of the paper is about compo sitionality and understanding, the second part is about compositionality an d lexical meaning.