Talking About Graphs

We introduce a general formal language in order to talk about properties of Kripke models. We then show how such languages can be defined in LoTREC and how to check that a formula is true in a given world of a given Kripke model. The latter is called model checking. Beyond model checking we also introduce the reasoning tasks of satisfiability checking, validity checking, and model building. We show that all other tasks can be reduced to the latter, which we focus on in the rest of the book: we show how to build models for a series of logics. These logics are grouped into families, according to the techniques the tableaux implementation in LoTREC requires.