Combining Texts

All the ideas for 'Against Theophrastus (frags)', 'Remarks on the definition and nature of mathematics' and 'A Completeness Theorem in Modal Logic'

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7 ideas

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]

5. Theory of Logic / E. Structures of Logic / 8. Theories in Logic

17807

To study formal systems, look at the whole thing, and not just how it is constructed in steps [Curry]

6. Mathematics / C. Sources of Mathematics / 4. Mathematical Empiricism / c. Against mathematical empiricism

17806

It is untenable that mathematics is general physical truths, because it needs infinity [Curry]

6. Mathematics / C. Sources of Mathematics / 6. Logicism / d. Logicism critique

17808

Saying mathematics is logic is merely replacing one undefined term by another [Curry]