Logical Disjunction - Union

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.

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Famous quotes containing the word union:

    “Our age is pre-eminently the age of sympathy, as the eighteenth century was the age of reason. Our ideal men and women are they, whose sympathies have had the widest culture, whose aims do not end with self, whose philanthropy, though centrifugal, reaches around the globe.”
    —Frances E. Willard 1839–1898, U.S. president of the Women’s Christian Temperance Union 1879-1891, author, activist. The Woman’s Magazine, pp. 137-40 (January 1887)

    “The man whose whole activity is diverted to inner meditation becomes insensible to all his surroundings. If he loves, it is not to give himself, to blend in fecund union with another being, but to meditate on his love. His passions are mere appearances, being sterile. They are dissipated in futile imaginings, producing nothing external to themselves.”
    —Emile Durkheim (1858–1917)

    “[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)