Combining Texts

All the ideas for 'fragments/reports', 'Why Propositions Aren't Truth-Supporting Circumstance' and 'Modal Logic'

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10 ideas

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]
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]
19. Language / C. Assigning Meanings / 2. Semantics
13965 Semantics as theory of meaning and semantics as truth-based logical consequence are very different [Soames]
19. Language / C. Assigning Meanings / 6. Truth-Conditions Semantics
13964 Semantic content is a proposition made of sentence constituents (not some set of circumstances) [Soames]
23. Ethics / A. Egoism / 1. Ethical Egoism
3031 The greatest good is not the achievement of desire, but to desire what is proper [Menedemus, by Diog. Laertius]