Talk:Boundary point
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every point is a boundary case
"...every point is a boundary case, or there is no boundary point at all — are both possible. In the first case the set is said to be dense in the space" — Really? The whole space is a (trivial) example of a dense set, but belongs to the latter case, not the former one. The condition "every point of the space is a boundary point of the given set" is equivalent rather to "the given set and its complement are both dense". Boris Tsirelson 09:18, 4 October 2009 (UTC)