After conversations with Drummond, it appears that there is a simpler way to model the access control semantics of a PolicyEntity. The new proposal is shown below and attached as a TIFF. Only one of the higgins:subject arcs shown below would be needed in the simplest case, but I drew both to show both possible kinds of subjects. As I hope is self-evident, the example below states that subject E3 and subject E4 are permitted <some kind of operation> (e.g. higgins:get, higgins:mod, higgins:del) on Entity E1 (that is, any or all Attributes of E1).
-Paul
