|Extensionality, philosophy: (also extensionality principle, extensionality thesis) an attempt to make the language distinct by taking complete sets of denoted objects as the meaning of the referring words. See also extensions, intensions, extensional language, ambiguity, propositional attitudes.|
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|Extensionality||Chisholm II 185
Extensionality/Quine: space time points instead of "durable goods" - SimonsVsQuine: language without continuants (permanent object) not learnable - Chisholm: probably time and modality, but not temporal or modal components: either a) accept phenomena, refuse extensionality or b) reject phenomena, demand extensionality for real lasting objects (> entia sukzessiva) - SimonsVsChisholm: better accept Aristotle things with unnecessary parts: trees simply consist of matter - more evidence than Wittgenstein's atoms.
Simons I 3
Extensionality/Simons: if it is rejected, more than one object can have exactly the same parts and therefore more than one object can be at the same time in the same place - then we are dealing with continuants.
continuant/Simons: everything which is not an event - (see below) everything that can have mass.
Extensional mereology/CEM/extensionality/Simons: characteristic property: relationship "part-of-or-identical-with" corresponds with "less-than-or-equal" relationship - Overlapping: can be used as the only fundamental concept - limiting case: separateness and identity.
Part/VsExtensional mereology/Simons: 1. whole sometimes not one of its own parts - 2. sometimes not transitive - 3. existence of "sum-individuals" not always guaranteed - that means, since the axioms, for individuals who obey any predicate, are wrong - 4. Identity criteria for individuals who have all parts in common, are wrong.
5. provides a materialist ontology of four-dimensional objects - Part/Simons: thesis: there is no uniform meaning of "part".
Extensionality/Simons: is left with the rejection of the proper parts principle - Proper parts principle.
Proper Parts Principle/strong/strong supporting principle: if x is not part of y, then there is a z which is part of x and which is separated from y - solution for distinguishing sum (Tib + Tail) and whole (process) Tibbles (cat) - ((s)intentionality, intentional mereology?) - Simons: coincidence of individuals: temporarily indistinguishable (perceptually) -> superposition: at the same time in the same place.
Parts Oxford New York 1987
Die erste Person Frankfurt 1992
Roderick M. Chisholm
Erkenntnistheorie Graz 2004