Combining Texts

All the ideas for 'fragments/reports', 'works' and 'Modal Logic'

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10 ideas

1. Philosophy / D. Nature of Philosophy / 6. Hopes for Philosophy

8226	A well-posed problem is a problem solved [Bergson, by Deleuze/Guattari]

4. Formal Logic / D. Modal Logic ML / 3. Modal Logic Systems / b. System K

14970

Normal system K has five axioms and rules [Cresswell]

4. Formal Logic / D. Modal Logic ML / 3. Modal Logic Systems / c. System D

14971

D is valid on every serial frame, but not where there are dead ends [Cresswell]

4. Formal Logic / D. Modal Logic ML / 3. Modal Logic Systems / g. System S4

14972

S4 has 14 modalities, and always reduces to a maximum of three modal operators [Cresswell]

4. Formal Logic / D. Modal Logic ML / 3. Modal Logic Systems / h. System S5

14973

In S5 all the long complex modalities reduce to just three, and their negations [Cresswell]

4. Formal Logic / D. Modal Logic ML / 7. Barcan Formula

14976

Reject the Barcan if quantifiers are confined to worlds, and different things exist in other worlds [Cresswell]

8. Modes of Existence / A. Relations / 4. Formal Relations / a. Types of relation

14974

A relation is 'Euclidean' if aRb and aRc imply bRc [Cresswell]

9. Objects / E. Objects over Time / 8. Continuity of Rivers

579	Cratylus said you couldn't even step into the same river once [Cratylus, by Aristotle]

10. Modality / A. Necessity / 4. De re / De dicto modality

14975

A de dicto necessity is true in all worlds, but not necessarily of the same thing in each world [Cresswell]

13. Knowledge Criteria / D. Scepticism / 1. Scepticism

578	Cratylus decided speech was hopeless, and his only expression was the movement of a finger [Cratylus, by Aristotle]