Combining Texts

All the ideas for 'Metaphysics', 'Letters to Oldenburg' and 'Modal Logic'

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11 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]
7. Existence / C. Structure of Existence / 8. Stuff / a. Pure stuff
16771 A composite is a true unity if all of its parts fall under one essence [Scheibler]
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 / 1. Nature of Ethics / f. Ethical non-cognitivism
4867 Whether nature is beautiful or orderly is entirely in relation to human imagination [Spinoza]
28. God / A. Divine Nature / 3. Divine Perfections
4866 God is a being with infinite attributes, each of them infinite or perfect [Spinoza]
28. God / B. Proving God / 3. Proofs of Evidence / e. Miracles
4868 Trying to prove God's existence through miracles is proving the obscure by the more obscure [Spinoza]