1. A pacing therapy system, comprising: an external communication device; a stimulation device adapted to communicate with the external communication device, the stimulation device comprising: one or more electrodes adapted to be placed on or near a nerve of an autonomic nervous system; a sensor that senses at least one of a physiological signal or a physical signal; a processing circuit that provides at least one of a current physiological level or a current physical level using the sensor; and a control circuit that causes the stimulation device to provide a stimulation according to a set of stimulation parameters; wherein the control circuit comprises a memory having a state transition model comprising a transition matrix and a connection matrix stored thereon, the transition matrix defining conditions for transitioning between particular states of a plurality of states of the state transition model and the connection matrix defining whether transitions between particular pairs of states are permitted, wherein the plurality of states are defined by a set of stimulation parameters and at least one of an expected physiological response or an expected physical response during application of the stimulation with the sets of stimulation parameters; wherein the control circuit is initialized from a learning phase whereby at least one of an actual physiological level or an actual physical level is determined and stored for a predetermined set of stimulation parameters used during the learning phase, and wherein the control circuit is configured to: for each set of stimulation parameters, raise a value of at least one of the actual physiological level or the actual physical level; order the plurality of states according to the at least one of the actual physiological level or the actual physical level; depending on the result of the ordering the plurality of states, assign to the set of stimulation parameters of each state a second set of stimulation parameters; and determine a plurality of stimulation instructions defined by transitions between sets of stimulation parameters in accordance with a target value for the at least one of the actual physiological level or the actual physical level.