|Principles, philosophy of science: physical principles are not the same as laws of nature. Rather, laws can be gained from principles or traced back to principles. Examples are the principle of the shortest time, the principle of the smallest effect, the uncertainty principle. See also theories, laws of nature, laws, natural constants.|
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Simons pro LP (Locke s principle, weak) - for substances: No two can be at the same place at the same time.
Falsehood principles / modal mereology / Kit Fine: in a possible world, where an object does not exist, every sentence is wrong, that says that this object has a part or is a part of something (not without truth value). - This also applies to overlapping, but not to separateness. - Def weakly separated / Simons: are objects when in a possible world either both exist or both do not exist there. - Def strongly separated / Simons: here one might demand, that the objects exist in a possible world in which they are separated. - This is just contrary, not contradictory to overlap. -> part-of-relation.
Parts Oxford New York 1987