Set theory, the mathematical study of collections of objects, forms a foundation for much of modern mathematics, while cardinal functions provide a means to quantify the sizes of these sets, ...

A Platonistic set theory with a universal set, CUSɩ, in the spirit of Alonzo Church's "Set Theory with a Universal Set," is presented; this theory uses a different sequence of restricted equivalence ...

We discuss several ontological properties of explicit mathematics and operational set theory: global choice, decidable classes, totality and extensionality of operations, function spaces, class and ...