List of Figures. Preface. 1. Action as Explanation. 2. Agency: Its Terms and Relations. 3. The Rational Processes of Agency. 4. The Semantics of Action. 5. A Design Document for PRAGMA. Appendix 1: Notation. Appendix 2: Part 1. Objects in the Logical Space of Action. Part 2. Agency Stream Profiles and their Corresponding Explanatory Objects. Notes. Glossary. Bibliography. Index.