In "Sense and Content", Peacocke assumed that the intentional content of mental states is exclusively conceptual content, i.e. the content is such that the subject of the state needs to possess all the concepts that specify the intentional content in question. From about 1986 and onwards, Peacocke abandoned this assumption, arguing that some mental states, in particular perceptual experiences and representational states implicated in subpersonal information processing (for example, in the subconscious parsing of heard speech), have non-conceptual intentional content. Peacocke is now often seen as a leading proponent of this notion of non-conceptual intentional content.