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B. Lellmann:
"Proof theory for deontic logic inspired by Indian Philosophy";
Keynote Lecture: Annual meeting of the Swiss Society for Logic and Philosophy of Science, Bern; 2019-10-24 - 2019-10-25.

The syntactic or proof-theoretic approach to the analysis of philsophical concepts such as "obligation" or "prohibition" often encounters a fundamental difficulty. On one side, for the formalisation of basic properties of such concepts it is convenient to use axioms in a Hilbert-style framework. On the other side, for checking that the formalisation is appropriate it is important to know its logical consequences - a task which lends itself to the use of automated reasoning methods. Unfortunately, axiomatic systems are not very suitable as a basis for automated reasoning. Hence there is more and more interest in general methods for the conversion of Hilbert-systems into formal calculi more suitable for automated proof search.
In this talk I will illustrate the power of such methods in the context of deontic logic. More specifically, I will present recent results in the project of formalising principles of deontic reasoning employed by the Mimamsa school of Indian Philosophy. The Mimamsa school reaches back more than 2000 years and constitutes one of the main schools of Indian Philosophy, with a major focus on the explication and analysis of the deontic content of the Indian sacred texts, the Vedas. Interestingly, many principles of deontic reasoning encountered in the Mimamsa texts are shared with the more modern formal approaches, rendering the resulting logics relevant to contemporary deontic logic. A particularly noteworthy feature is a form of non-monotonic reasoning used to resolve conflicts between deontic assumptions via the specificity principle. Apart from the theoretical results I will further present a prototype implementation of the resulting deontic logic.