Colloque : Towards a History Of Sound-Symbolic Theories (THOSST2014), P. Monneret & L. Nobile (org.), Université de Dijon, 20-21 février 2014, à paraîtreOne of the foundations of Gustave Guillaume’s (1883-1960) Psychomechanics is the idea that language is the product of the combination of two indissociable structures, the semiological structure (the signifier1) and the psychic structure (the signified), linked by a “congruency” relation (Guillaume 1971: 170):A principle adhered to by all the languages in their construction is that of congruency or, in other words, the matching between the signifier and the signified. The signifier is an act of speech, the signified an act of thought, and the structure of a language, and its very existence, ...