Abstract: A control method and apparatus (30) for controlling a real time industrial process of which the operation can be defined by a set of P logical statements of the formSTATE.sub.(N) AND OMI.sub.(N,M) =STATE.sub.(M)whereN and M may have any integral value up to P,N does not equal M,STATE.sub.(N), OMI.sub.(N,M), and STATE.sub.(M) are all logical variables, andOMI.sub.(N,M) is the conjunctive OPERATING MODE INCREMENT that is necessary to the progress of the process from STATE.sub.(N) to STATE.sub.(M),and in which set only one such STATE variable at a time can be recognized as having the value TRUE.