  The most venerable approach to demarcating the logical constants identifies them with the language’s syncategorematic signs: signs that signify nothing by themselves, but serve to indicate how independently meaningful terms are combined. This approach was natural in the context of the “term logics” that were dominant until the nineteenth century. All propositions were thought to be composed out of propositions of subject-predicate form by means of a small number of connectives (“and”, “or”, “if …then”, and so on). In this framework, words divide naturally into those that can be used as subjects or predicates (“categorematic” words) and those whose function is to indicate the relation between subject and predicate or between two distinct subject-predicate propositions (“syncategorematic” words). For example, “Socrates”, “runs”, “elephant”, and “large” are categorematic words, while “only”, “every”, “necessarily”, and “or” are syncategorematic. (For a more detailed account of the distinction, see Kretzmann 1982, 211–214.) The syncategorematic words were naturally seen as indicating the structure or form of the proposition, while the categorematic words supplied its “matter.” Thus the fourteenth-century logician Buridan writes: