«The larger the variety of actions available to a control system, the larger the variety of perturbations it is able to compensate.»
Said briefly, this law tells us that a system's ability to control cannot exceed its capacity as a communication channel. This means that our ability of control is decided by our ability to process and communicate information. It also implies that if we are to adjust to changes, our behavioral pattern must be as varied as the patterns in the changes we are exposed to. Only variety can overcome variety.