Rules of a rule base are transformed in an automated fashion in order to be able to conduct consistency checks and generate explanations and thus classify and correct existing rules. This is beneficial in particular in large systems with existing rule bases, e.g., wherein each rule is associated with at least a diagnostic task of a component of a technical system, e.g., a power system. The task can be subject to fault detection, fault isolation, predictive diagnosis or reporting. The solution presented provides an overview of large sets of rules and thus allows determining which rules are suitable and which are not. The invention is applicable for all kinds of technical systems, e.g., industry and automation systems, in particular power systems.