Symbol
The mathematical symbol for logical disjunction varies in the literature. In addition to the word "or", and the formula "Apq", the symbol "", deriving from the Latin word vel for "or", is commonly used for disjunction. For example: "A B " is read as "A or B ". Such a disjunction is false if both A and B are false. In all other cases it is true.
All of the following are disjunctions:
The corresponding operation in set theory is the set-theoretic union.
Read more about this topic: Logical Disjunction
Famous quotes containing the word symbol:
“A symbol is indeed the only possible expression of some invisible essence, a transparent lamp about a spiritual flame; while allegory is one of many possible representations of an embodied thing, or familiar principle, and belongs to fancy and not to imagination: the one is a revelation, the other an amusement.”
—William Butler Yeats (1865–1939)
“Whatever we inherit from the fortunate
We have taken from the defeated
What they had to leave us—a symbol:
A symbol perfected in death.”
—T.S. (Thomas Stearns)
“There is that in me—I do not know what it is—but I know it is in me ...
I do not know it—it is without name—it is a word unsaid,
It is not in any dictionary, utterance, symbol ...
Do you see O my brothers and sisters?
It is not chaos or death—it is form, union, plan—it is eternal life—it is Happiness.”
—Walt Whitman (1819–1892)