Tag Archives: Bertrand Russell

Everything and nothing

This is a response to Volkan’s comment. Nothing The mathematician says: Theorem There is only one empty set. Proof Two sets are equal if they have exactly the same elements. (This is a version of Leibniz’s principle of identity of … Continue reading

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Mathematical structures, 2

The second week of the course has been and gone. We started on the real business this week, with a chapter about sets. Although I didn’t quite finish this rather long chapter in a week (the next one will be … Continue reading

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