Union
The union used in set theory is defined in terms of a logical disjunction: x ∈ A ∪ B if and only if (x ∈ A) ∨ (x ∈ B). Because of this, logical disjunction satisfies many of the same identities as set-theoretic union, such as associativity, commutativity, distributivity, and de Morgan's laws.
Read more about this topic: Logical Disjunction
Famous quotes containing the word union:
“We are constantly thinking of the great war ... which saved the Union ... but it was a war that did a great deal more than that. It created in this country what had never existed before—a national consciousness. It was not the salvation of the Union, it was the rebirth of the Union.”
—Woodrow Wilson (1856–1924)
“The old ideals are dead as nails—nothing there. It seems to me there remains only this perfect union with a woman—sort of ultimate marriage—and there isn’t anything else.”
—D.H. (David Herbert)
“The methods by which a trade union can alone act, are necessarily destructive; its organization is necessarily tyrannical.”
—Henry George (1839–1897)