Not for sale

The reason that you will not find these puzzles in the stores is that you can not make them with a sharp knife or other precision tools. They are purely theoretic puzzles that can be constructed with some algebra and knowledge of infinite sets.

The puzzles of Hausdorff, Banach and Tarski are a bit hard to describe; There are simplified versions that are not so spectacular but that can be described in a few paragraphs.
Last modified: Wednesday 26-02-2003 at 13:08:35 (CET)