In mathematics, and more specifically set theory, the empty set is the unique set having no elements; its size or cardinality (count of elements in a set) is zero. Some axiomatic set theories assure that the empty set exists by including an axiom of empty set; in other theories, its existence can be deduced. Many possible properties of sets are trivially true for the empty set.
Null set was once a common synonym for "empty set", but is now a technical term in measure theory.
Read more about Empty Set: Notation, Properties
Famous quotes containing the words empty and/or set:
“In the Lord’s Prayer, the first petition is for daily bread. No one can worship God or love his neighbor on an empty stomach.”
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“Groot: Now wait a minute, Quo. You really ain’t gonna take a man’s only set of teeth, are ya?
Quo: Uh huh.
Groot: Yeah, but I gotta use ‘em for eatin’.
Quo: Come grub you get ‘em.
Groot: Whad ya’ gonna do with ‘em?
Quo: My name now Two-Jaw Quo.”
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