Why the empty set is a subset of every set?
36721
Is "The empty set is a subset of any set" a convention?
110485
Nested sequence of non-empty compact subsets - intersection differs from empty set
147136
Subset of a countable set is itself countable
47123
Suppose that a set has an odd number of elements. Explain why half of the subsets will have an odd number of elements
65308
Axiom of Choice: Family of non-empty sets mutually disjoint or not?
46317
What is an Empty set?
125317
Is this statement "Every element in the empty set is greater than itself." true or its negation is true?
10472
Is every set a subset?
125502
Empty set literal?
47562
Confusion in symbol of subset.
84609
Unary intersection of the empty set
50258
How can a set contain itself?
99480
Why is predicate "all" as in all(SET) true if the SET is empty?
110677
How is an empty set truly "empty"?
26008
Why there is a unique empty set?
88205
How can I define a topology on the empty set?
31212
The existence of the empty set is an axiom of ZFC or not?