Structural rule A famous structural rule is known as cut. Considerable effort is spent by proof theorists in showing that cut rules are superfluous in various logics. More precisely, what is shown is that cut is only (in a sense) a tool for abbreviating proofs, and does not add to the theorems that can be proved. The successful 'removal' of cut rules, known as "cut elimination", is directly related to the philosophy of "computation as normalization" (see Curry–Howard correspondence); it often gives a good indication of the complexity of deciding a given logic. Structural rule In proof theory, a structural rule is
Offshore Racing Congress Rule produce the extreme and often unsafe designs which became the hallmark of the IOR rule. To encourage the growth of the rule, two versions have been developed. The ORC-International rule (ORCi) is the full complexity, highly developed version for top level championship racing. An ORC-Club rule has also been developed, which is a simplified version more easily used by smaller clubs who have less resources. Offshore Racing Congress Rule The Offshore Racing Congress Rule is a system of handicapping sailboats for the purpose of racing. It is managed by the Offshore Racing Congress (ORC) and is usually referred to in