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)
“The rage for road building is beneficent for America, where vast distance is so main a consideration in our domestic politics and trade, inasmuch as the great political promise of the invention is to hold the Union staunch, whose days already seem numbered by the mere inconvenience of transporting representatives, judges and officers across such tedious distances of land and water.”
—Ralph Waldo Emerson (1803–1882)
“If the union of these States, and the liberties of this people, shall be lost, it is but little to any one man of fifty-two years of age, but a great deal to the thirty millions of people who inhabit these United States, and to their posterity in all coming time.”
—Abraham Lincoln (1809–1865)