In ZFC, are all sets hereditary?
22498
In set theory, how are real numbers represented as sets?
30587
Uncountable well ordered set in $Z^-$ theory.
63276
Is an arbitrary union of a chain of countable sets countable?
136755
Direct proof of empty set being subset of every set
21938
describing all possible topologies on a set
17624
Axiom of Choice iff Every set has a choice function
135524
Is $\mathrm{ZFC}^E$ outright inconsistent?
155063
Is Cl(f(A)) a subset of f(Cl(A))?
120376
Schema of separation and set of all sets
85398
$\mathsf{ZF}$ is not finitely axiomatizable
130771
Sets and the principle of inclusion and exclusion
61747
Proof of exchange principle in set theory
20706
Non-existence of a Surjective Function from a Set to Its Subsets (Cantor's theorem)
69838
Does a countably infinite power set exist?
29755
Power set equivalency of Axiom of Choice
136835
ZF Set Theory - If $|A|^{|B|} = |B|$, then $|A| = 1 = |B|.$
31212
The existence of the empty set is an axiom of ZFC or not?