A Comment on Argumentation

We use the theory of defaults and their meaning of [GS16] to develop (the outline of a) new theory of argumentation

A pre-semantics for counterfactual conditionals and similar logics

The elegant Stalnaker/Lewis semantics for counterfactual conditonals works with distances between models. But human beings certainly have no tables of models and distances in their head. We begin here an investigation using a more realistic picture, based on findings in neuroscience. We call it a pre-semantics, as its meaning is not a description of the world, but of the brain, whose structure is (partly) determined by the world it reasons about. In the final section, we reconsider the components, and postulate that there are no atomic pictures, we can always look inside

A remark on utility streams

We consider arbitrarily long, but finite utility streams, and some appropriate axioms

Conditionals and modularity in general logics

In this work in progress, we discuss independence and interpolation and related topics for classical, modal, and non-monotonic logics

Reactive preferential structures and nonmonotonic consequence

We introduce information bearing systems (IBRS) as an abstraction of many logical systems. We define a general semantics for IBRS, and show that IBRS generalize in a natural way preferential semantics and solve open representation problems

Factorization (Splitting)

We show some elementary facts about the semantical analogue of Parikh's Splitting, which we call Factorization

Semantic interpolation

We treat interpolation for various logics

Equilibria und weiteres Heiteres

We investigate several technical and conceptual questions

Independence - revision and defaults

We investigate different aspects of independence here, in the context of theory revision, generalizing slightly work by Chopra, Parikh, and Rodrigues, and in the context of preferential reasoning