|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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Logical possibility / Dennett: e.g. Superman flies faster than light,this is logically possible - Dupermann who does not move while he flies faster than light, is not logically possible.
Problem: how to distinguish logical and physical possibility: e.g. time travel.
Possibility / graduation / degree / Dennett: at least 4 degrees:
1 logical possibility
4.historical. (Nested in that order.) The weakest is the purely logical possibility.
Darwins gefährliches Erbe Hamburg 1997
Spielarten des Geistes Gütersloh 1999