How can a class not be a set?
3482
What are the differences between class, set, family, and collection?
141299
Alternative set theories
5230
Why can a 1 element set be a member of another set but not a subset of it?
27022
The difference between Classes, Objects, and Instances
100245
Category of Grp is not a subcategory of Set
114968
Partition of a set, definition not clear
49147
Showing that the class of all sets of a particular cardinality is not a set.
120367
Why is there a class keyword in C++?
20706
Non-existence of a Surjective Function from a Set to Its Subsets (Cantor's theorem)
48546
How dangerous is setting self.__class__ to something else?
67064
Uncountable minus countable set is uncountable
62208
If $A$ is a non-empty set, then $A \notin A$
88099
Not $\sigma$-compact set without axiom of choice
106414
Classifying whether a collection of objects is a set
134050
Question about set notation: what does $]a,b[$ mean?
93750
Can a set be neither open nor closed?
122048
why is the set of all binary sequences not countable?