Full Idea
It is one thing to say that P is necessary in some generic sense because it is a truth of logic (true in all models of a language, perhaps). It is something else to say that P therefore enjoys a special sort of necessity.
Gist of Idea
Something may be necessary because of logic, but is that therefore a special sort of necessity?
Source
Gideon Rosen (The Limits of Contingency [2006], 02)
Book Reference
'Identity and Modality', ed/tr. MacBride,Fraser [OUP 2006], p.15
A Reaction
This encourages my thought that there is only one sort of necessity (what must be), and the variety comes from the different types of necessity makers (everything there could be, nature, duties, promises, logics, concepts...).