Universal Set

A set fixed within the framework of a theory and consisting of all objects considered in this theory.

The complement of the universal set is the empty set.

See also

Empty Set, Finite Set

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References

Fraenkel, A. A. and Bar-Hillel, Y. Foundations of Set Theory. Amsterdam, Netherlands, 1958.

Referenced on Wolfram|Alpha

Cite this as:

Weisstein, Eric W. "Universal Set." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/UniversalSet.html

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