Abstract
This paper argues that negative polarity items like any and ever are words which constrain mental processes in the sense of Blakemore (1987), and this may be viewed as an NPI-licensing condition. These words require that a proposition corresponding to an utterance containing NPIs should be processed in what I call the cognitive structure of negation. Relevance theory, proposed by Sperber and Wilson (1986), provides an adequate way of describing this mental process. The infelicity of NPIs in certain environments which would pose problems for Ladusaw (1979) is explicable under my analysis. It leads us to an interesting claim about the human congnitive processing procedure.
