On a sequence of contradiction-tolerating logics
pp. 125-139
in: Roberto Poli (ed), Consciousness, knowledge, and truth, Berlin, Springer, 1993Abstract
In recent years, logicians have been increasingly interested in logical frameworks within which one can discuss the thesis that some contradictions may be jointly true.1 This thesis which is most often attributed to the great German idealist philosopher W.G. Hegel, probably, because it was Hegel who expressed it in the most forceful and sophisticated way (see [1] and [2]). This thesis, to be called the contradiction thesis hereafter, has since been subjected to many criticisms. The most severe criticism followed by a total rejection of the thesis comes from the modern formal-logical direction. It was initiated by B. Russell (see [6]) at the beginning of the century and then continued by many contemporary analytic philosophers including K. Popper whose influential paper [3] may be seen as the most expressive attempt to ridicule the thesis. The main point of this criticism is that the thesis cannot be consistently accommodated within a language understood in a classical-logical way.
