Combining Texts

All the ideas for 'Aristotle and Descartes on Matter', 'Introduction to a Secret Encyclopaedia' and 'A Completeness Theorem in Modal Logic'

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

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7 ideas

1. Philosophy / F. Analytic Philosophy / 2. Analysis by Division

13099

Analysing right down to primitive concepts seems beyond our powers [Leibniz]

3. Truth / A. Truth Problems / 8. Subjective Truth

5022	We hold a proposition true if we are ready to follow it, and can't see any objections [Leibniz]

4. Formal Logic / D. Modal Logic ML / 1. Modal Logic

10163

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

10760

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

16189

The variable domain approach to quantified modal logic invalidates the Barcan Formula [Kripke, by Simchen]

15132

The Barcan formulas fail in models with varying domains [Kripke, by Williamson]

26. Natural Theory / A. Speculations on Nature / 6. Early Matter Theories / b. Prime matter

19399

Prime matter is nothing when it is at rest [Leibniz]