Combining Texts

All the ideas for 'The Gettier Problem', 'Psychophysical and theoretical identifications' 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]
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 / A. Justification Problems / 2. Justification Challenges / b. Gettier problem
19699 A Gettier case is a belief which is true, and its fallible justification involves some luck [Hetherington]
26. Natural Theory / D. Laws of Nature / 4. Regularities / b. Best system theory
9409 Laws are the best axiomatization of the total history of world events or facts [Lewis, by Mumford]
9423 If simplicity and strength are criteria for laws of nature, that introduces a subjective element [Mumford on Lewis]
9424 A number of systematizations might tie as the best and most coherent system [Mumford on Lewis]