Infinitary logic logical axiom, an element of T, or is deduced from previous statements using a rule of inference. As before, all rules of inference in finitary logic can be used, together with an additional one: The logical axiom schemata specific to infinitary logic are presented below. Global schemata variables: formula_3 and formula_18 such that formula_23. The last two axiom schemata require the axiom of choice because certain sets must be well orderable. The last axiom schema is strictly speaking unnecessary as Chang's distributivity laws imply it, however it is included as a natural way to allow natural weakenings to the logic.
State logic State logic A state logic control system is a programming method created for PLCs. A state logic control system uses a state transition diagram as a model of reality, thus using the fundamentals of finite-state machine theory as the basis of a programming language. State logic enables users to model the application they are trying to control by using a hierarchy that consists of Tasks, subdivided by States which are described by Statements. 'Tasks' are a description of a sequential activity of the model. The machines, applications or processes being modelled by state logic will usually contain more than one