|Possible World: entity that can be quantified over. There ist a dispute over the question whether possible worlds exist or are only assumed for purposes of proofs of completeness. See also actual world, modal logic, modal realism, realism, actualism, possibility, possibilia, quantification.|
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Possible Worlds/Popper: There are logically infinitely many possible worlds. The system that we call "empirical science" is supposed to represent ("experienced reality") only one "real world." Three demands:
1. it must be synthetical (represent a non-contradictory world).
2. it must not be metaphysical (represent a possible "Experience World").
3. must be somehow excellent over other systems.
Objektive Erkenntnis Hamburg 1993