A Medieval Theory of Supposition

A MEDIEVAL THEORY OF SUPPOSITION* INTRODUCTION Supposition and signification are technical terms in medieval semantics . Since Supposition cannot be understood without the more basic term of signification, it is necessary first to acquaint ourselves with the elements of the scholastic theory of signification. For obvious reasons, the discussion of signification will be confined to the realm of language. The broader aspect of signification will therefore be disregarded, and hence no general theory of signs or symbols will be discussed here. But only those signs and symbols which are elements of language, that is, words or terms will be studied.1 Words or terms belong to the class of language signs. Language signs are characterized as follows: They are sounds, produced by the vocal apparatus of rational animals and signifying some object by convention.2 These signs constitute our spoken language. Strictly speaking, two kinds of words are required to construct compositions of wordswhich arecalled sentences (propositiones), viz., the noun and the verb. A noun is a term that signifies an object as such without also signifying the time. A verb is a term which signifies an object and also the time. The composition of a noun and a verb is called a sentence, that is, a composition of terms of which it is meaningful to ask whether it is true or false. This is the initial material a logician needs. However, in order to be able to construct his logic he is in need of other language signs, which * When Fr. Philotheus Boehner died, in 1955, he was working on the present study, with the intention to have it published in the collection Studies in Logic and the Foundations of Mathematics of the North-Holland Publishing Company. We publish the study unfinished as it was, but edited by one of his former students. 1 A comprehensive medieval theory of signs would concern natural physical and biological signs (smoke signifies fire; pulse or sighing signifies health or pain) ; or the arbitrary or conventional signs which are not words (as for instance, the barrel hoop signifies wine) ; or finally the religious signs, which are the sacraments, sacramentáis and the symbols of liturgy. 2 Cfr. Petrus Hispanus, Summulae logicales, ed. Bochenski 102: in vox est sonus ab ore animalis prolatus, naturalibus instrumentis formatus . . . Cfr. also 1. 03: Vocum alia litterata, alia non litterata. Vox litterata est, quae scribi potest . . . Vocum litteratarum alia est significativa, alia non significativa. Vox significativa est illa, quae auditui aliquid repraesentat, ut "homo" vel gemitus infirmorum, qui dolorem significat. 240 A Medieval Theory of Supposition241 he also calls 'nouns,' though they are not in complete agreement with our definition. In order to make their distinction clear and to analyze the semantical relations, we shall make a new start. a. Signification of categorematic terms From the viewpoint of logic two main groups of nouns must be distinguished, categorematic and syncategorematic terms. Categorematic terms signify definite and certain objects; syncategorematic terms do not signify certain objects, when taken alone, but they signify objects only in conjunction with categorematic terms. Categorematic terms are, for instance, the terms 'man,' 'stone,' etc.; syncategorematic terms are, for instance, the terms 'every,' 'not,' 'is.'3 What are the semantical relations of categorematic terms ? As signs they must satisfy the definition of a sign: A sign is something which when apprehended calls something to the mind. To take a simple or rather simplified example, let us assume that someone intelligently hears the word "tree." In this case, we distinguish a mind (M) that apprehends a word (W) which brings or presents to the mind a certain object (O). Thus signification is the relation of presenting (Pr) between a mind, a word and an object. We symbilize this triadic basic relation of the signification of a word (Sigw) as follows: Sigw = Def. Pr (W, O, M) But there is another relation within the relation of signification and which complicates the former relation. A clear distinction must be made between signification and meaning, or the signification and the sense of a word. Meaning is taken here in the sense of a concept, as the scholastics understood it; other words for concepts were "understanding" (intellectus), "impression of the mind...