[FOM] Is ZF interpretable in ZF minus extensionality plus X inaccessibles?

[Frode Bjørdal]

As I understand it ZF is not interpretable in ZF minus extensionality;
a reference here is Scott, D., "More on the Axiom of Extensionality,"
pp. 115-131 in Essays on the Foundations of Mathematics, edited by Y.
Bar-Hillel, et al., Hebrew University, Jerusalem, 1966.

Does someone know if ZF is interpretable in ZF minus extensionality
plus some amount of inaccessibles? If it is, what is the lowest amount
needed?

-- 
Frode Bjørdal
Professor i filosofi
IFIKK, Universitetet i Oslo
www.hf.uio.no/ifikk/personer/vit/fbjordal/index.html