Combining Texts

All the ideas for 'Modal Logic', 'Fifteen Sermons' and 'Review of Bob Hale's 'Abstract Objects''

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10 ideas

1. Philosophy / F. Analytic Philosophy / 4. Conceptual Analysis
9184 We can't presume that all interesting concepts can be analysed [Williamson]
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]
6. Mathematics / C. Sources of Mathematics / 1. Mathematical Platonism / a. For mathematical platonism
9183 Platonism claims that some true assertions have singular terms denoting abstractions, so abstractions exist [Williamson]
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]
22. Metaethics / A. Ethics Foundations / 2. Source of Ethics / c. Ethical intuitionism
8066 Butler exalts conscience, but it may be horribly misleading [Anscombe on Butler]