Combining Texts

All the ideas for 'Space and Time', 'There Are No Abstract Objects' 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]
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]
8. Modes of Existence / E. Nominalism / 1. Nominalism / c. Nominalism about abstracta
14596 Call 'nominalism' the denial of numbers, properties, relations and sets [Dorr]
8. Modes of Existence / E. Nominalism / 5. Class Nominalism
14597 Natural Class Nominalism says there are primitive classes of things resembling in one respect [Dorr]
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]
10. Modality / A. Necessity / 11. Denial of Necessity
14598 Abstracta imply non-logical brute necessities, so only nominalists can deny such things [Dorr]
27. Natural Reality / C. Space / 6. Space-Time
14014 Space alone, and time alone, will fade away, and only their union has an independent reality [Minkowski]