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All the ideas for 'Exigency to Exist in Essences', 'Causation' and 'Logical Necessity'

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29 ideas

4. Formal Logic / D. Modal Logic ML / 3. Modal Logic Systems / h. System S5
The logic of metaphysical necessity is S5 [Rumfitt]
5. Theory of Logic / B. Logical Consequence / 1. Logical Consequence
Soundness in argument varies with context, and may be achieved very informally indeed [Rumfitt]
There is a modal element in consequence, in assessing reasoning from suppositions [Rumfitt]
We reject deductions by bad consequence, so logical consequence can't be deduction [Rumfitt]
5. Theory of Logic / D. Assumptions for Logic / 3. Contradiction
Contradictions include 'This is red and not coloured', as well as the formal 'B and not-B' [Rumfitt]
5. Theory of Logic / H. Proof Systems / 2. Axiomatic Proof
Geometrical axioms in logic are nowadays replaced by inference rules (which imply the logical truths) [Rumfitt]
7. Existence / A. Nature of Existence / 5. Reason for Existence
Possibles demand existence, so as many of them as possible must actually exist [Leibniz]
God's sufficient reason for choosing reality is in the fitness or perfection of possibilities [Leibniz]
8. Modes of Existence / C. Powers and Dispositions / 2. Powers as Basic
If dispositions are more fundamental than causes, then they won't conceptually reduce to them [Bird on Lewis]
10. Modality / A. Necessity / 3. Types of Necessity
A distinctive type of necessity is found in logical consequence [Rumfitt, by Hale/Hoffmann,A]
10. Modality / A. Necessity / 6. Logical Necessity
Logical necessity is when 'necessarily A' implies 'not-A is contradictory' [Rumfitt]
A logically necessary statement need not be a priori, as it could be unknowable [Rumfitt]
Narrow non-modal logical necessity may be metaphysical, but real logical necessity is not [Rumfitt]
10. Modality / B. Possibility / 9. Counterfactuals
For true counterfactuals, both antecedent and consequent true is closest to actuality [Lewis]
10. Modality / E. Possible worlds / 1. Possible Worlds / a. Possible worlds
The actual universe is the richest composite of what is possible [Leibniz]
10. Modality / E. Possible worlds / 1. Possible Worlds / e. Against possible worlds
If a world is a fully determinate way things could have been, can anyone consider such a thing? [Rumfitt]
16. Persons / F. Free Will / 6. Determinism / a. Determinism
Determinism says there can't be two identical worlds up to a time, with identical laws, which then differ [Lewis]
19. Language / D. Propositions / 2. Abstract Propositions / b. Propositions as possible worlds
A proposition is a set of possible worlds where it is true [Lewis]
26. Natural Theory / C. Causation / 5. Direction of causation
A theory of causation should explain why cause precedes effect, not take it for granted [Lewis, by Field,H]
I reject making the direction of causation axiomatic, since that takes too much for granted [Lewis]
26. Natural Theory / C. Causation / 8. Particular Causation / d. Selecting the cause
It is just individious discrimination to pick out one cause and label it as 'the' cause [Lewis]
The modern regularity view says a cause is a member of a minimal set of sufficient conditions [Lewis]
26. Natural Theory / C. Causation / 9. General Causation / a. Constant conjunction
Regularity analyses could make c an effect of e, or an epiphenomenon, or inefficacious, or pre-empted [Lewis]
26. Natural Theory / C. Causation / 9. General Causation / c. Counterfactual causation
The counterfactual view says causes are necessary (rather than sufficient) for their effects [Lewis, by Bird]
Lewis has basic causation, counterfactuals, and a general ancestral (thus handling pre-emption) [Lewis, by Bird]
Counterfactual causation implies all laws are causal, which they aren't [Tooley on Lewis]
My counterfactual analysis applies to particular cases, not generalisations [Lewis]
One event causes another iff there is a causal chain from first to second [Lewis]
26. Natural Theory / D. Laws of Nature / 9. Counterfactual Claims
Lewis's account of counterfactuals is fine if we know what a law of nature is, but it won't explain the latter [Cohen,LJ on Lewis]