Aatu Koskensilta wrote: > Lester Zick wrote: > > Jesuits are also very fond of faith based mathematics. > > Mice are fond of cheese, as we learn in inner model theory. > > -- > Aatu Koskensilta (firstname.lastname@example.org) > > "Wovon man nicht sprechen kann, daruber muss man schweigen" > - Ludwig Wittgenstein, Tractatus Logico-Philosophicus
I checked out that core model, with the mice and premice and pistols and so on, there are still the same problems as there are in other regular set theories with no universe.
That seems particularly so where the basic idea of model theory is that there is a "universal" ordinal of sorts, the model. Do you remember yet?
There is no universe in ZF. There are no non-set classes in pure set theory and no models are necessary in theory. Numbers are naturally ordered.