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Ideas for 'works', 'Truthmakers and Converse Barcan Formula' and 'The World as Will and Idea'

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4 ideas

4. Formal Logic / D. Modal Logic ML / 3. Modal Logic Systems / h. System S5
If metaphysical possibility is not a contingent matter, then S5 seems to suit it best [Williamson]
     Full Idea: In S5, necessity and possibility are not themselves contingent matters. This is plausible for metaphysical modality, since metaphysical possibility, unlike practical possibility, does not depend on the contingencies of one's situation.
     From: Timothy Williamson (Truthmakers and Converse Barcan Formula [1999], §1)
     A reaction: This is the clearest statement I have found of why S5 might be preferable for metaphysics. See Nathan Salmon for the rival view. Williamson's point sounds pretty persuasive to me.
4. Formal Logic / D. Modal Logic ML / 7. Barcan Formula
If the domain of propositional quantification is constant, the Barcan formulas hold [Williamson]
     Full Idea: If the domain of propositional quantification is constant across worlds, the Barcan formula and its converse hold.
     From: Timothy Williamson (Truthmakers and Converse Barcan Formula [1999], §2)
     A reaction: So the issue is whether we should take metaphysics to be dealing with a constant or varying domains. Williamson seems to favour the former, but my instincts incline towards the latter.
Converse Barcan: could something fail to meet a condition, if everything meets that condition? [Williamson]
     Full Idea: The converse Barcan is at least plausible, since its denial says there is something that could fail to meet a condition when everything met that condition; but how could everything meet that condition if that thing did not?
     From: Timothy Williamson (Truthmakers and Converse Barcan Formula [1999], §3)
     A reaction: Presumably the response involves a discussion of domains, since everything in a given domain might meet a condition, but something in a different domain might fail it.
4. Formal Logic / G. Formal Mereology / 1. Mereology
Aristotle relativises the notion of wholeness to different measures [Aristotle, by Koslicki]
     Full Idea: Aristotle proposes to relativise unity and plurality, so that a single object can be both one (indivisible) and many (divisible) simultaneously, without contradiction, relative to different measures. Wholeness has degrees, with the strength of the unity.
     From: report of Aristotle (works [c.330 BCE]) by Kathrin Koslicki - The Structure of Objects 7.2.12
     A reaction: [see Koslicki's account of Aristotle for details] As always, the Aristotelian approach looks by far the most promising. Simplistic mechanical accounts of how parts make wholes aren't going to work. We must include the conventional and conceptual bit.