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:
“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)
“To emancipate [the slaves] entirely throughout the Union cannot, I conceive, be thought of, consistently with the safety of the country.”
—Frances Trollope (1780–1863)
“Should the German people lay down their arms, the Soviets ... would occupy all eastern and south-eastern Europe together with the greater part of the Reich. Over all this territory, which with the Soviet Union included, would be of enormous extent, an iron curtain would at once descend.”
—Joseph Goebbels (1897–1945)