Rules
Most proof systems provide ways to deduce one sequent from another. These inference rules are written with a list of sequents above and below a line. This rule indicates that if everything above the line is true, so is everything under the line.
A typical rule is:
This indicates that if we can deduce that yields, and that yields, then we can also deduce that yields .
Read more about this topic: Sequent
Famous quotes containing the word rules:
“Different rules apply when it gets this late. You know what I mean? It’s, like, after hours.”
—Joseph Minion, U.S. screenwriter, and Martin Scorsese. Peter (Rocco Sisto)
“But suppose, asks the student of the professor, we follow all your structural rules for writing, what about that “something else” that brings the book alive? What is the formula for that? The formula for that is not included in the curriculum.”
—Fannie Hurst (1889–1968)
“However patriarchal the world, at home the child knows that his mother is the source of all power. The hand that rocks the cradle rules his world. . . . The son never forgets that he owes his life to his mother, not just the creation of it but the maintenance of it, and that he owes her a debt he cannot conceivably repay, but which she may call in at any time.”
—Frank Pittman (20th century)