著者

今井 知正

出版者

日本西洋古典学会

雑誌

西洋古典學研究 (ISSN:04479114)

巻号頁・発行日

vol.26, pp.89-97, 1978-03-23

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According to my diagnosis, when we try to solve problems of Aristotle's modal syllogistic, a key to them, lies in a semantical analysis of which of the three-terminterpretations for 'proof by contrasted instances' and 'proof by instances' is applied to non-modal propositions of each of his syllogisms. I. The analysis of proof by contrasted instances in the case of the non-modal syllogisms shows that the non-modal propositions here are clearly regarded as those which can also be interpreted as necessary propositions. II. On the analysis of proof by instances in the case of the syllogisms with one necessary and one non-modal premiss, we can conclude that the non-modal propositions here are characteristically posited as true in at least one possible world accessible to the real world, on the ground that they are true in the latter as admissible propositions in the strict sense. III. Exactly speaking, there is only one example of proof by instances in the case of the syllogisms with one admissible and one non-modal premiss. Therefore let us direct our attention to his restriction on the term-interpretation in An. Pr. 34b7-18. From a logical point of view, then, this restriction is opposed to the definition of a valid syllogism as dependent only on its logical structure. From a philosophical point of view, on the other hand, it gives rise to the serious problem that the formal language level in which, proper to An. Pr., no semantical distinction is drawn between categories, is confused with another language level which contains this distinction.