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Name: yendor
Status: N/A
Age: N/A
Location: N/A
Country: N/A
Date: Around 1995

I heard that not every collection of objects is a set. I was wondering if you could give an example of such a selection collection, and explain why it is not a set.

I have also seen such a remark made in very pedantic math books. I think the idea is to avoid the "set of all sets" paradox. That is, the collection of all sets is not a set. That is because "set" does not properly describe a property of a "objects" that can be collected into sets. Ordinary mortals need not worry about the distinction.


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