 What Humboldt describes here is a dual process of segmentation: that of the mental stream of impressions and a corresponding one of sensory order, exactly what linguists today refer to as the “principle of double articulation” (Martinet 1963: 22f). Through reflection we single out “certain portions” from the unending and amorphous flow of impressions and mental images while at the same time imposing an order upon them. This imposition of order is the work of the sensory medium of language: word sounds function as structured units (Einheiten) through which we discern and secure the mental units in the flow of impressions and images. Human speech, therefore, is no longer seen by Humboldt as applying and manipulating a fixed system of arbitrary signs as was assumed by both rationalists and empiricists, but consists rather of the operation of joining together these two different sets of orders: that of the articulated sound, the signifier, and that of the “thought” or signified. Over a century later Saussure in his Cours de Linguistique Générale would define language and the linguistic sign with almost the same words. What constituted language, according to Saussure, was