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:
“[With the Union saved] its form of government is saved to the world; its beloved history, and cherished memories, are vindicated; and its happy future fully assured, and rendered inconceivably grand.”
—Abraham Lincoln (1809–1865)
“My whole working philosophy is that the only stable happiness for mankind is that it shall live married in blessed union to woman-kind—intimacy, physical and psychical between a man and his wife. I wish to add that my state of bliss is by no means perfect.”
—D.H. (David Herbert)
“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)