Combining Texts

All the ideas for 'Necessary Existents', 'Gentzen's Analysis of First-Order Proofs' and 'Classes and Attributes'

expand these ideas     |    start again     |     specify just one area for these texts

---

5 ideas

5. Theory of Logic / A. Overview of Logic / 1. Overview of Logic

13831

Logic is based on transitions between sentences [Prawitz]

5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / a. Logical connectives

13825

Natural deduction introduction rules may represent 'definitions' of logical connectives [Prawitz]

5. Theory of Logic / H. Proof Systems / 4. Natural Deduction

13823

In natural deduction, inferences are atomic steps involving just one logical constant [Prawitz]

8. Modes of Existence / B. Properties / 11. Properties as Sets

9783	While no two classes coincide in membership, there are distinct but coextensive attributes [Cartwright,R]

19. Language / D. Propositions / 3. Concrete Propositions

19216

Propositions (such as 'that dog is barking') only exist if their items exist [Williamson]