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:
“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)
“Thus piteously Love closed what he begat:
The union of this ever-diverse pair!
These two were rapid falcons in a snare,
Condemned to do the flitting of the bat.”
—George Meredith (1828–1909)
“What should concern Massachusetts is not the Nebraska Bill, nor the Fugitive Slave Bill, but her own slaveholding and servility. Let the State dissolve her union with the slaveholder.... Let each inhabitant of the State dissolve his union with her, as long as she delays to do her duty.”
—Henry David Thoreau (1817–1862)