 James was the first champion of NEP. He endorsed it in the course of repudiating the ‘mind-stuff theory’, according to which “our mental states are composite in structure, made up of smaller states conjoined” (1890: 145). Against this James says that, while our experience is complex, this complexity is not a matter of there being several experiences (or ‘feelings’) present in an encompassing experience. This is because “we cannot mix feelings as such, though we may mix the objects we feel, and from their mixture get new feelings” (1890: 157). If one’s experience appears to become more complex, that is a matter of a single experience’s content being more complex, and is not the addition of more experiences (of the diverse contents). Indeed, he says, “We cannot even … have two feelings in mind at once” (1890: 157).