effective procedure
In logic, an effective procedure is a procedure for solving problem by any intuitively ‘effective’ means from a specific class.
(wff: well-formed formula)
FR1FR2FR3. A variable standing alone is a wff. If α is a wff, so is ¬α. If α and β are wffs, then (α⋅β),(α β),(α∨β),(α⊃β), and (α≡β) are wffs