Editing Modal logic (section)

====Metaphysical possibility====
{{Main|Modal metaphysics}}
[[Philosophers]]{{who|date=April 2012}} debate if objects have properties independent of those dictated by scientific laws. For example, it might be metaphysically necessary, as some who advocate [[physicalism]] have thought, that all thinking beings have bodies<ref>{{cite web|last1=Stoljar|first1=Daniel|title=Physicalism|url=http://plato.stanford.edu/entries/physicalism/|website=The Stanford Encyclopedia of Philosophy|access-date=16 December 2014}}</ref> and can experience the passage of [[time]]. [[Saul Kripke]] has argued that every person necessarily has the parents they do have: anyone with different parents would not be the same person.<ref>Saul Kripke ''Naming and Necessity'' Harvard University Press, 1980, p. 113.</ref>

[[Metaphysical possibility]] has been thought to be more restricting than bare logical possibility<ref>{{cite book|last1=Thomson|first1=Judith and Alex Byrne|title=Content and Modality : Themes from the Philosophy of Robert Stalnaker|date=2006|publisher=[[Oxford University Press]]|location=Oxford|page=107|url=https://books.google.com/books?id=JXeOkXnCwb8C|access-date=16 December 2014|isbn=9780191515736}}</ref> (i.e., fewer things are metaphysically possible than are logically possible). However, its exact relation (if any) to logical possibility or to physical possibility is a matter of dispute. Philosophers{{who|date=April 2012}} also disagree over whether metaphysical truths are necessary merely "by definition", or whether they reflect some underlying deep facts about the world, or something else entirely.