In Classical Logic and Boolean Logic
Boolean logic defines the false in both senses mentioned above: "0" is a propositional constant, whose value by definition is 0. In a classical propositional calculus, depending on the chosen set of fundamental connectives, the false may or may not have a dedicated symbol. Such formulas as p ∧ ¬p and ¬(p → p) may be used instead.
In both systems the negation of the truth gives false. The negation of false is equivalent to the truth not only in classical logic and Boolean logic, but also in most other logical systems, as explained below.
Read more about this topic: False (logic)
Famous quotes containing the words classical and/or logic:
“Et in Arcadia ego.
[I too am in Arcadia.]”
—Anonymous, Anonymous.
Tomb inscription, appearing in classical paintings by Guercino and Poussin, among others. The words probably mean that even the most ideal earthly lives are mortal. Arcadia, a mountainous region in the central Peloponnese, Greece, was the rustic abode of Pan, depicted in literature and art as a land of innocence and ease, and was the title of Sir Philip Sidney’s pastoral romance (1590)
““... We need the interruption of the night
To ease attention off when overtight,
To break our logic in too long a flight,
And ask us if our premises are right.””
—Robert Frost (1874–1963)