Table of Contents

§0 The pre-history of the topic.- §1 The grammar of the Q systems.- §2 The semantics of the Q systems.- §3 Descriptions.- §4 Statability atoms.- §5 Relevance conditions.- §6 Some irrefutable and refutable sentences.- §7 The Q calculi.- §8 Basic metatheorems on the Q calculi.- §9 Deductions. Further derived rules.- §10 Consistent and complete sets.- §11 Hypercomplete and compossible sets.- §12 Alternatives and successors of hypercomplete sets.- §13 Tree structures.- §14 The completeness theorem.- Appendix 1: Deontic logic.- References.- List of symbols.- List of abbreviations.