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:
“Some are petitioning the State to dissolve the Union, to disregard the requisitions of the President. Why do they not dissolve it themselves,—the union between themselves and the State,—and refuse to pay their quota into its treasury? Do not they stand in the same relation to the State that the State does to the Union? And have not the same reasons prevented the State from resisting the Union which have prevented them from resisting the State?”
—Henry David Thoreau (1817–1862)
“Let’s have the Union restored as it was, if we can; but if we can’t, I’m in favor of the Union as it wasn’t.”
—Artemus Ward (1834–1867)
“You can no more keep a martini in the refrigerator than you can keep a kiss there. The proper union of gin and vermouth is a great and sudden glory; it is one of the happiest marriages on earth, and one of the shortest-lived.”
—Bernard Devoto (1897–1955)