An Artificial Reasoning System Dealing with Thales of Miletus’ Theory of the Soul

Abstract The theory of the soul attributed to Thales of Miletus presents a complexity. It seems to imply a contradiction. Thales appears to state that the beings devoid of a soul possess a soul. This claim causes problems with its logical consideration. At least, it reveals problems if it is addressed within the framework of classical logic. In this paper, I try to show that those problems do not exist in Non-Axiomatic Logic. Due to its concept of extensional difference, the latter logic can deal with seemly contradictory theses such as that ascribed to Thales of Miletus. This is because extensional difference allows building compound terms that can be related to simple terms that, in principle, are inconsistent with them.