Ideas from 'Logical Necessity: Some Issues' by Ian McFetridge [1986], by Theme Structure

[found in 'Logical Necessity' by McFetridge,Ian G. [Aristotelian Soc 1990,0-907111-24-6]].

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10. Modality / A. Necessity / 6. Logical Necessity
Logical necessity overrules all other necessities
The fundamental case of logical necessity is the valid conclusion of an inference [Hale]
In the McFetridge view, logical necessity means a consequent must be true if the antecedent is [Hale]
Logical necessity requires that a valid argument be necessary
Traditionally, logical necessity is the strongest, and entails any other necessities
It is only logical necessity if there is absolutely no sense in which it could be false
The mark of logical necessity is deduction from any suppositions whatever
10. Modality / B. Possibility / 2. Epistemic possibility
We assert epistemic possibility without commitment to logical possibility
10. Modality / C. Sources of Modality / 1. Sources of Necessity
Objectual modal realists believe in possible worlds; non-objectual ones rest it on the actual world
10. Modality / C. Sources of Modality / 5. Modality from Actuality
Modal realists hold that necessities and possibilities are part of the totality of facts