Algebraic Set TheoryThis book offers a new algebraic approach to set theory. The authors introduce a particular kind of algebra, the Zermelo Fraenkel algebras, which arise from the familiar axioms of Zermelo Fraenkel set theory. Furthermore, the authors explicitly construct these algebras using the theory of bisimulations. Their approach is completely constructive, and contains both intuitionistic set theory and topos theory. In particular it provides a uniform