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Superposition/Simons: different individuals with identical parts at the same time in the same place. - SimonsVsQuine: instead of "content of one portion RZ" - Such occupiers must be continuants anyway. - Events: among them the extensionality principle is fulfilled - masses: need different meanings of "part".
Superposition instead of coincidence: E.g. Ring/Gold. - E.g. person/body. - Not two individuals, but relation one-much. - They are not identical, but take the same space - E.g. Ring/Gold: different stories.
Superposition/SimonsVsWiggins: that various objects can superimpose follows from the fact that a single piece of material can be in such a state that it simultaneously fulfills different existence conditions. - ((S) So intensional). - Existence conditions: are determined by the sortal term. - (lo linguistically) different existence conditions: things can last for different times. - And still be at the same red. - E.g. (s) an astronaut in the orbit can become uncle.
Superposition/Doepke/Simons: whenever a and b are superimposed, they must have a common part, they must be composed entirely of a third party, c.
Parts Oxford New York 1987