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:
“My Christian friends, in bonds of love, whose hearts in sweetest union join,
Your friendship’s like a drawing band, yet we must take the parting hand.
Your company’s sweet, your union dear; Your words delightful to my ear,
Yet when I see that we must part, You draw like cords around my heart.”
—John Blain (18th century)
“If the Union is once severed, the line of separation will grow wider and wider, and the controversies which are now debated and settled in the halls of legislation will then be tried in fields of battle and determined by the sword.”
—Andrew Jackson (1767–1845)
“Our age is pre-eminently the age of sympathy, as the eighteenth century was the age of reason. Our ideal men and women are they, whose sympathies have had the widest culture, whose aims do not end with self, whose philanthropy, though centrifugal, reaches around the globe.”
—Frances E. Willard 1839–1898, U.S. president of the Women’s Christian Temperance Union 1879-1891, author, activist. The Woman’s Magazine, pp. 137-40 (January 1887)