Gödel's modal ontological argument is the centerpiece of an extensive examination of intensional logic. First, classical type theory is presented semantically, tableau rules for it are introduced, and the Prawitz/Takahashi completeness proof is given. Then modal machinery is added to produce a modified version of Montague/Gallin intensional logic. Finally, various ontological proofs for the existence of God are discussed informally, and the Gödel argument is fully formalized. Parts of the book are mathematical, parts philosophical.

Preface. Part I: Classical Logic. 1. Classical Logic - Syntax. 2. Classical Logic - Semantics. 3. Classical Logic - Basic Tableaus. 4. Soundness and Completeness. 5. Equality. 6. Extensionality. Part II: Modal Logic. 7. Modal Logic, Syntax and Semantics. 8. Modal Tableaus. 9. Miscellaneous Matters. Part III: Ontological Arguments. 10. Gödel's Argument, Background. 11. Gödel's Argument, Formally. References. Index.