Full Idea
The truthmaker theorist's 'concrete' states of affairs must be distinguished from necessarily existing 'abstract' states of affairs.
Gist of Idea
We must distinguish 'concrete' from 'abstract' and necessary states of affairs.
Source
Theodore Sider (Writing the Book of the World [2011], 08.4)
Book Reference
Sider,Theodore: 'Writing the Book of the World' [OUP 2011], p.154
A Reaction
[He cites Plantinga's 'Nature of Necessity' for the second one; I presume the first one is Armstrong]