聖トマスに於けるesseとexistereについて (完) : Existereの意味の探究、結論及追記

Abstract

The distinction established by St. Thomas Aquinas between ESSE and ESSENTIA has been shifted by later scholastics to the distinction between EXISTENTIA and ESSENTIA. The aim of this study was to clarify whether ESSE may rightly be identified with EXISTENTIA, by conducting a thorough examination of the various usages of the terms ESSE and EXISTERE throughout the main works of Saint Thomas Aquinas. The conclusions arrived at are as follows : 1) ESSE is not "actus existendi" but "actus essendi". In itself a potency to ESSE, ESSENTIA becomes not only an actual existence but also an actual essence through its actualisation by ESSE. For examp'e, the ESSENTIA of a horse through its actualisation by ESSE not only actually exists but also actually is a horse. Thus "actus essendi" may connotate "actus existendi", but these are not to be identified with one another. 2) (a) EXISTERE etymologically means "to stand from out.････". We should say that EXISTENCE stands from out the actualisation of ESSENCE by ESSE; thus the same ESSENTIA is to be found under different modes of existing according to different ESSE through which it is actualised. For example, the ESSENTIA of a horse, when actualised through real esse, comes into real existence in accordance with the mode of real being ("equus existit in rerum natura") ; whereas when actualised through intellectual esse, it comes into intellectual existence in accordance with the mode of intellectual being ("conceptus equi existit in intellectu"). (b) On the other hand, the same ESSE may appear under different modes of existing according to different ESSENTIA which it actualises. For example, the ESSE as such of a complete human being and of a separated human soul is the same, but the ESSENTIA actua-lised in each case is not the same, for the former is a perfect essence ("essentia composita ex anima et corpore', ) whereas the latter is an imperfect one ("essentia animae separatae"); so that their modes of existing are not the same. 3) ESSENTIA is related to ESSE as a potency to an act, whereas EXISTERE is related to ESSE as an effect to a cause. So that it would seem legitimate to remark that the identification of ESSE with EXISTERE would lead to serious misunderstandings as to the very meaning of ESSE in Saint Thomas Aquinas.