In between the two polarically opposite systems there is a third, again of clearly distinct character, which functions as a mediator between the two. Here all processes are of a strictly rhythmic nature, as is shown by the process of breathing and the pulsation of the blood. This system, too, provides the foundation for a certain type of psychological process, namely feeling. That feeling is an activity of the soul distinct from both thinking and willing, and that it has its direct counterpart in the rhythmic processes of the body, can be most easily tested through observing oneself when listening to music.