We prove that the problem of determining the minimum propositional proof length is NP- hard to approximate within a factor of 2 log1 - o (1)n. These results are very robust in that they hold for ...

Description: Intelligent industrial systems. Expert-system and knowledge-based decision and control examples. Propositional logic, resolution principle for deduction, Horn-clause systems of logic, ...

Truth diagrams (TDs) are introduced as a novel graphical representation for propositional logic (PL). To demonstrate their epistemic efficacy a set of 28 concepts are proposed that any comprehensive ...

Outline of topics Ever since modern symbolic logic was consolidated (in the mid 1900s), the standard format for an introductory logic class has been to learn the classical predicate calculus in three ...