Full Idea
A metaphysically necessary proposition is one that is true in virtue of the essential nature of things.
Gist of Idea
Metaphysical necessities are those depending on the essential nature of things
Source
Brian Ellis (The Metaphysics of Scientific Realism [2009], 6)
Book Reference
Ellis,Brian: 'The Metaphysics of Scientific Realism' [Acument 2009], p.116
A Reaction
It take this to be what Kit Fine argues for, though it tracks back to Aristotle. I also take it to be correct, though one might ask whether there are any other metaphysical necessities, ones not depending on essences.