Combining Texts

All the ideas for 'fragments/reports', 'Modal Logic within Counterfactual Logic' and 'Reductive Theories of Modality'

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9 ideas

1. Philosophy / D. Nature of Philosophy / 3. Philosophy Defined

9218	Maybe what distinguishes philosophy from science is its pursuit of necessary truths [Sider]

4. Formal Logic / D. Modal Logic ML / 3. Modal Logic Systems / h. System S5

14626

In S5 matters of possibility and necessity are non-contingent [Williamson]

9. Objects / E. Objects over Time / 8. Continuity of Rivers

579	Cratylus said you couldn't even step into the same river once [Cratylus, by Aristotle]

10. Modality / A. Necessity / 1. Types of Modality

14625

Necessity is counterfactually implied by its negation; possibility does not counterfactually imply its negation [Williamson]

10. Modality / B. Possibility / 8. Conditionals / a. Conditionals

14623

Strict conditionals imply counterfactual conditionals: □(A⊃B)⊃(A□→B) [Williamson]

10. Modality / B. Possibility / 9. Counterfactuals

14624

Counterfactual conditionals transmit possibility: (A□→B)⊃(◊A⊃◊B) [Williamson]

10. Modality / C. Sources of Modality / 1. Sources of Necessity

14531

Rather than define counterfactuals using necessity, maybe necessity is a special case of counterfactuals [Williamson, by Hale/Hoffmann,A]

13. Knowledge Criteria / D. Scepticism / 1. Scepticism

578	Cratylus decided speech was hopeless, and his only expression was the movement of a finger [Cratylus, by Aristotle]

15. Nature of Minds / C. Capacities of Minds / 2. Imagination

14628

Imagination is important, in evaluating possibility and necessity, via counterfactuals [Williamson]