Abstract
The subject of this report is a border region between two languages: that of the Zen kōan and that of formal logic. Firstly, I present part of a classic work of Zen Buddhism, the Hekiganroku (Biyen-lu, 碧巌録) with some additional commentary. Secondly, I put forward a possible means of translating Zen kōans into the language of formal logic. This exposition is tied to a three-fold problematic: Is it possible to say that the different logics (of the language of Zen and the language of formal logic) agree in their logical essence? If so, in which aspects can we find these points of agreement? Or do they represent only different parallel logics without any points of crossing? What is the definitive difference between their respective ways of thinking? The answers to these questions may providecontemporary buddhist philosophy with a further perspective: how Zen thought can stimulate and contribute to formal logic. The transcription of Zen kōan into formal logical symbols is able to clarify what is the most important subject in the language of Zen. At the same time it will show the limitations of the language of formal logic and the language of Zen kōan. In my report I try to delineate the limits of verbal expression in formal logic and explore what is the truth expressed in nonverbal applications of Zen logic. A new way of thinking can emerge from the field between the logic of verbal and of non-verbal expression.