The connecting paths between the theories of knowledge, of signs, and of grammar were trodden so many times: PortRoyal produced its Grammaire as a complement and natural sequel to its Logique, the former being connected to the latter by a common analysis of signs; Condillac, Destutt de Tracy, and Gerando articulated one upon the other the decomposition of knowledge into its conditions or 'elements', and the reﬂection upon those signs of which language forms only the most visible application and use.