Combining Texts

All the ideas for 'fragments/reports', 'Logicism in the 21st Century' and 'A Completeness Theorem in Modal Logic'

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


10 ideas

4. Formal Logic / D. Modal Logic ML / 1. Modal Logic
Propositional modal logic has been proved to be complete [Kripke, by Feferman/Feferman]
4. Formal Logic / D. Modal Logic ML / 3. Modal Logic Systems / a. Systems of modal logic
With possible worlds, S4 and S5 are sound and complete, but S1-S3 are not even sound [Kripke, by Rossberg]
4. Formal Logic / D. Modal Logic ML / 7. Barcan Formula
The variable domain approach to quantified modal logic invalidates the Barcan Formula [Kripke, by Simchen]
The Barcan formulas fail in models with varying domains [Kripke, by Williamson]
6. Mathematics / B. Foundations for Mathematics / 5. Definitions of Number / d. Hume's Principle
Neo-logicism founds arithmetic on Hume's Principle along with second-order logic [Hale/Wright]
6. Mathematics / B. Foundations for Mathematics / 5. Definitions of Number / e. Caesar problem
The Julius Caesar problem asks for a criterion for the concept of a 'number' [Hale/Wright]
6. Mathematics / C. Sources of Mathematics / 6. Logicism / a. Early logicism
Logicism is only noteworthy if logic has a privileged position in our ontology and epistemology [Hale/Wright]
6. Mathematics / C. Sources of Mathematics / 6. Logicism / c. Neo-logicism
Logicism might also be revived with a quantificational approach, or an abstraction-free approach [Hale/Wright]
18. Thought / E. Abstraction / 7. Abstracta by Equivalence
One first-order abstraction principle is Frege's definition of 'direction' in terms of parallel lines [Hale/Wright]
21. Aesthetics / C. Artistic Issues / 7. Art and Morality
Musical performance can reveal a range of virtues [Damon of Ath.]