中世纪两种语义学及其现代重建

Two Medieval Semantics and Their Modern Re-construction

以西班牙的彼得为代表的实在论语义学和以布里丹为代表的唯名论语义学代表了中世纪逻辑领域两种不同的完整语义学。然而,它们在语义学上的不同并不在于其本体论基础或本体论承诺,而在于建构语义学的方法与思路,即范式。我们可以通过不同的逻辑策略消除实在论语义学中不必要的本体论承诺,从而在逻辑学领域实现两者的部分融合;唯名论语义理论因之可以通过副词化的手段从实在论语义学中获得。而对两种语义学合理的现代重建,既可表明唯名论与实在论的区别,又可表明唯名论语义学如何用纯粹自然逻辑的方式恰当地表达现代逻辑标准量词理论。

Abstract： Peter of Spain＇s realism and John Buridan＇s nominalism are generally taken as the two predominant complete medieval semantics. However, the real difference between them does not lie in ontology,but rather in their paradigms of constructing semantic theories. For realists, they insist on a one-to-one mapping of linguistic terms with ontological categories, i. e. a singular term signifies an individual item while a universal term signifies a general item, both of which are taken as a substantial existence. However, in the eyes of nominalists, there is no place for universal items, everything in the world is singular, and everything that exists is numerically one and undivided. Singular and universal terms would not differ in the type of entities they signify, hut rather in the way they signify the same type of entities. In other words, both singular term and universal term are applied to signify individual items： a singular term signifies things in a singular manner, whereas a universal adverbialization term signifies things in a universal manner. The latter is a key semantic strategy named＂ ＇ when we deal with the significata of a universal term. Furthermore, the semantic strategy of ＂adverbialization＂ is also extensively applied to the significata of connotative terms. Based on the different principles of term signification, the two semantics have totally different theories of propositional significata and truth-conditions. Realists are ontologically committed to the total significata of the proposition taken as a whole, particularly the significata of the complex terms or connotative terms in the proposition, and hence defines truth in terms of the actuality or non-actuality of these significata. For nominalist, by contrast, no such type of entities -- propositions signifying complex significata- actually exists or should be asserted. What a proposition signifies is no more than what each term in it signifies. However, they are by no means useful in dealing with the semantic evaluation of propositions. Hence, by adverbializing universal terms as well as connotative terms, and introducing quantifiers, nominalists assign the truth conditions of a proposition in terms of whether or not the terms in it co-signify the same individual thing in the domain to which the quantifiers are restricted. In a semantic construction of this sort, neither the subject nor the predicate would be committed to universal entities or propositional significata for truth value. As a result of these logical tactics on the contrary, any unwanted or unnecessary ontological commitments are eliminated by realists. We can then neglect the difference between the two semantics and focus on the possibility and operability of realist semantics being at least partially integrated into nominalism. Generally speaking, nominalism is obtainable by the adverbialization of realist semantics. A rational modern re-construction is probably the best way to facilitate the comparison between the two medieval semantics, as well as their comparison with the competing modern quantification theory in so far as how nominalism semantics can be modified to represent the standard modern semantics merely by natural logic. The theory of NLS （natural language system） is such a complete semantics system based on the formalization of nominalism natural language semantics. NLS, which is devised to describe the nominalist notions and principles of term signification and co-supposition, provides an easily operable program to construct a natural semantics and to represent the multi-quantifier theory of the first order logic, in so far as it is infinitely close to the pure-natural-language based conventional human thinking. Furthermore, it is not necessary for NLS to carry out the semantic function of the predicates with an ontological commitment of sets, like what modern logic does. The construction of NLS follows the trend of advocating natural methods for the problems within natural logic. This is probably one of the main significances or innovations of this paper.