 The manuscript partially completed during these years and published posthumously as The Prose of the World (1969/1973) pursues these themes through a phenomenological investigation of literary language and its relationship with scientific language and painting. Critiquing our commonsense ideal of a pure language that would transparently encode pre-existing thoughts, Merleau-Ponty argues that instituted language—the conventional system of language as an established set of meanings and rules—is derivative from a more primordial function of language as genuinely creative, expressive, and communicative. Here he draws two insights from Saussurian linguistics: First, signs function diacritically, through their lateral relations and differentiations, rather than through a one-to-one correspondence with a conventionally established meaning. Ultimately, signification happens through the differences between terms in a referential system that lacks any fixed or positive terms. This insight into diacritical difference will later prove important to Merleau-Ponty’s understanding of perception and ontology as well (see Alloa 2013a). Second, the ultimate context for the operation of language is effective communication with others, by which new thoughts can be expressed and meanings shared. Expression accomplishes itself through a coherent reorganization of the relationships between acquired signs that must teach itself to the reader or listener, and which may afterwards again sediment into a taken-for-granted institutional structure.