Full Idea
Mirimanoff: φ(x) is 'x is well founded', so that w is the cumulative hierarchy of sets, V; &delta(x) is just the power set of x, P(x). If x⊆V, then V∈V and V∉V, since δ(V) is just V itself.
Gist of Idea
The next set up in the hierarchy of sets seems to be both a member and not a member of it
Source
Graham Priest (The Structure of Paradoxes of Self-Reference [1994], §2)
Book Reference
-: 'Mind' [-], p.27