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10. Modality / A. Necessity / 3. Types of Necessity

[different ways in which things must be]

24 ideas
A stone travels upwards by a forced necessity, and downwards by natural necessity [Aristotle]
The only necessity is logical necessity [Wittgenstein]
Necessities are distinguished by their grounds, not their different modalities [Ellis]
We should not multiply senses of necessity beyond necessity [Jackson]
There is 'absolute' necessity (implied by all propositions) and 'relative' necessity (from what is given) [Harré/Madden]
Strong necessity is always true; weak necessity is cannot be false [Stalnaker]
Logical possibility contains metaphysical possibility, which contains nomological possibility [Salmon,N]
The three basic types of necessity are metaphysical, natural and normative [Fine,K]
'Conceptual' necessity is narrow logical necessity, true because of concepts and logical laws [Lowe]
Logical necessities, based on laws of logic, are a proper sub-class of metaphysical necessities [Lowe]
Maybe not-p is logically possible, but p is metaphysically necessary, so the latter is not absolute [Hale]
'Relative' necessity is just a logical consequence of some statements ('strong' if they are all true) [Hale]
A strong necessity entails a weaker one, but not conversely; possibilities go the other way [Hale]
'Strong' necessity in all possible worlds; 'weak' necessity in the worlds where the relevant objects exist [Sider]
'Absolute necessity' is when there is no restriction on the things which necessitate p [Hale]
Logical and metaphysical necessities differ in their vocabulary, and their underlying entities [Hale]
Absolute necessities are necessarily necessary [Hale]
Analytic truths are divided into logically and conceptually necessary [Girle]
Is 'events have causes' analytic a priori, synthetic a posteriori, or synthetic a priori? [Baggini /Fosl]
If the laws necessarily imply p, that doesn't give a new 'nomological' necessity [Bird]
Relevant necessity is always true for some situation (not all situations) [Beall/Restall]
Physical possibility is part of metaphysical possibility which is part of logical possibility [Rami]
Superficial necessity is true in all worlds; deep necessity is thus true, no matter which world is actual [Schroeter]
A distinctive type of necessity is found in logical consequence [Hale/Hoffmann,A on Rumfitt]