Modality
Links
Stanford Encyclopedia of Philosophy: Modal Fictionalism
http://plato.stanford.edu/entries/fictionalism-modal/
Survey of the view that claims of necessity and possibility are to be construed as fictional claims; by Daniel Nolan.
Stanford Encyclopedia of Philosophy: Actualism
http://plato.stanford.edu/entries/actualism/
The thesis that there are no merely possible entities; by Christopher Menzel.
Modal Realism
Examines the implications of modal realism for ontology.