Preface; Summary and plan of the book; 1. Logic on the Underground; 2. The psychology of logic; 3. The fox and the crow; 4. Search; 5. Negation as failure; 6. How to become a British citizen; 7. The louse and the Mars explorer; 8. Maintenance goals as the driving force of life; 9. The meaning of life; 10. Abduction; 11. The prisoner's dilemma; 12. Motivations matter; 13. The changing world; 14. Logic and objects; 15. Biconditionals; 16. Computational logic and the selection task; 17. Meta-logic; Conclusions of the book; References; Index.