Practice question · Multiple choice
and are both empty. Why is there only ONE empty set rather than two?
Hints
- Ask what makes two sets equal.
- The description is not the set.
Show the answer
A. Because a set is determined entirely by its members
Why
Extensionality: same members, same set. The two conditions are different sentences picking out the same object, which is why "the" empty set is correct.
Practise Sets and Set-Builder Notation
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