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:
“I would save the Union. I would save it the shortest way under the Constitution. The sooner the national authority can be restored; the nearer the Union will be “the Union as it was.””
—Abraham Lincoln (1809–1865)
“If the Union is now dissolved it does not prove that the experiment of popular government is a failure.... But the experiment of uniting free states and slaveholding states in one nation is, perhaps, a failure.... There probably is an “irrepressible conflict” between freedom and slavery. It may as well be admitted, and our new relations may as be formed with that as an admitted fact.”
—Rutherford Birchard Hayes (1822–1893)
“Visitors who come from the Soviet Union and tell you how marvellous it is to be able to look at public buildings without advertisements stuck all over them are just telling you that they can’t decipher the cyrillic alphabet.”
—Clive James (b. 1939)