Some books refer to themselves. Most do not.
Suppose I publish a book which is an index of books that do not refer to themselves.
Question: does that index refer to itself?
(Now that you mention it, I think Russell talked about index cards, which wouldn't really make sense to more modern readers)
Some books refer to themselves. Most do not.
Suppose I publish a book which is an index of books that do not refer to themselves.
Question: does that index refer to itself?