Order of Precedence
As a way of reducing the number of necessary parentheses, one may introduce precedence rules: ¬ has higher precedence than, higher than, and higher than →. So for example, P Q ¬R → S is short for (P (Q (¬R))) → S.
Here is a table that shows a commonly used precedence of logical operators.
-
Operator Precedence ¬ 1 2 3 → 4 5
The order of precedence determines which connective is the "main connective" when interpreting a non-atomic formula.
Read more about this topic: Logical Connectives
Famous quotes containing the words order and/or precedence:
“Like other cities created overnight in the Outlet, Woodward acquired between noon and sunset of September 16, 1893, a population of five thousand; and that night a voluntary committee on law and order sent around the warning, “if you must shoot, shoot straight up!””
—State of Oklahoma, U.S. public relief program (1935-1943)
“What is line? It is life. A line must live at each point along its course in such a way that the artist’s presence makes itself felt above that of the model.... With the writer, line takes precedence over form and content. It runs through the words he assembles. It strikes a continuous note unperceived by ear or eye. It is, in a way, the soul’s style, and if the line ceases to have a life of its own, if it only describes an arabesque, the soul is missing and the writing dies.”
—Jean Cocteau (1889–1963)