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
Mischief rule they are interpreting. Driedger puts it this way: "[T]o this day, "Heydon's Case" is frequently cited. The courts still look for the 'mischief' and 'remedy', but now use what they find as aids to discover the meaning of what the legislature has said rather than to change it." Driedger goes on to argue that this modern use of the mischief rule ought to be understood as one of the components of what he characterized as the "modern" method of statutory construction, rather than a stand-alone rule serving (as it formerly had), as an alternative to the methods of construction proposed