Is the Axiom of Empty Set a canonical ZFC axiom?
31212
The existence of the empty set is an axiom of ZFC or not?
103314
Let $\{K_n \}_{n \in \mathbb{N}}$ be a collection of sets, where $K_n = [n, \infty)$. Why is $\bigcap_{n \in \mathbb{N}} K_{n}$ empty?
30587
Uncountable well ordered set in $Z^-$ theory.
858
Is $\{\emptyset\}$ a subset of $\{\{\emptyset\}\}$?
85769
Do you need the Axiom of Choice to accept Cantor's Diagonal Proof?
132692
Nonempty set mapped to $\emptyset$ and vice-versa
74860
Why is the empty set a subset of every set?
18828
Base and empty set of a topology
58285
Is it true that if $X$ is connected, then for every nonempty proper subset $A$ of $X$, we have $\mathbf{Bd} \ne \emptyset$
149926
ZFC with class terms: is any set also a class?
77548
Given an arbitrary infinite set $S$, how to construct an injection $\mathbb{N} \to S$ with the Axiom of Choice?
153935
A weaker Axiom of Infinity?
27107
intersection of the empty set and vacuous truth
156252
Are sets constructed using only ZF measurable using ZFC?
82315
is an empty set an element of {empty set}
51687
Is the set $ \ (\mathbb{Z}_p \setminus \mathbb{Z}) \cap \mathbb{Q}$ non-empty?
142219
Does the splitting lemma hold without the axiom of choice?