Union and Intersection
If A and B are disjoint sets, then
From this, one can show that in general the cardinalities of unions and intersections are related by
Read more about this topic: Cardinality
Famous quotes containing the words union and/or intersection:
“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)
“If we are a metaphor of the universe, the human couple is the metaphor par excellence, the point of intersection of all forces and the seed of all forms. The couple is time recaptured, the return to the time before time.”
—Octavio Paz (b. 1914)