Saussure's Nachlass challenges the official Saussurean doctrine from the Course in General Linguistics with its hierarchical oppositions between la langue and la parole and synchrony and diachrony. It underscores the inescapably dual character of language that intersects relative stability with temporal change. This inescapable duality can be rendered more concrete by studying linguistic creativity. Called "analogical innovation" (or "creation"), linguistic creativity consists in a production of innovative forms of expression on the basis of established ones. Importantly, while the doctrinal view chases creativity outside of the language system, which is thought to be relatively autonomous and fixed, Saussure considers innovation an intrinsic feature of language (la langue) itself. Linguistic innovation cannot be discounted as a contingent empirical process. It is intrinsic to the functioning language system, and it furnishes a cardinal principle of general linguistics. Furthermore, linguistic innovation illustrates how the speakers' expressions (la parole) affect and alter the language system from within, as if rewriting its code. The dual essence of language—the intersection of stability and change—becomes grounded in speech practices that borrow existing linguistic resources and return them in a slightly revised format.