1. A method of controlling a process using a three-state four-mode process controller including the steps of providing a desired value signal to said process controller related to the condition to which it is desired to set said process, providing a feedback signal to said process controller from the process being controlled indicating the current condition of the process, providing a reset state signal to said process controller adapted to insure that the process controller can be easily reset to a state one condition as desired, which causes said process controller to begin operation in its first state producing a correction signal causing the process device which changes the condition of the process to operate at a predetermined rapid speed in a first desired direction, utilizing said desired value, feedback, and reset state signals to cause said process controller to change to its second state of operation when the error difference between said desired value and said feedback signal changes polarity thereby producing a correction signal causing said process device to operate at a predetermined rapid speed in the opposite direction, utilizing said error difference, the rate of change of said error difference, and the reset state signal to cause said process controller to change to its third state of operation when the summation of said error difference and said rate of change of said error difference changes polarity, producing a correction signal from said desired value and said feedback signals while said process controller is in its third state which will look ahead and attempt to become saturated as soon as a new desired value is supplied or a process change occurs by utilizing said rate of change and said error difference, which will remain unchanged as long as the process being controlled, and said desired value signal both remain unchanged and in a static condition, which will, if saturated, be brought out of saturation by utilizing said error difference and said rate of change in a manner to change said correction signal in value much faster than if said error difference only were used, and which will, if said process is in a dynamic condition, be changed in a series of occurrences to a value smaller in magnitude, but of either polarity, until it arrives at a value related to said condition it is desired to set said process to, and utilizing said correction signal to cause said process to arrive at said desired condition.