I have taken an interest in mathematical logic to understand to source of mathematics as we know it today. And in this regard I have the following two questions:
- What would a logical structure/interpretation look like for the Zermelo-Frankel axioms?
- How is it possible to define a logical structure if we don't know anything about functions or sets yet? To be clearer, objects like functions or sets follow from the Zermelo-Frankel axioms, but these objects are already used in the definitions of structures and interpretations before we even know that these objects exist.