If it is true to say that there exists in the relations between the soul and the body adomain where cause and effect, determinism and expression are still so tightly interwoven that in practice they form a single movement which will only be undone later on; if it is also true that preceding the violence of the body and the quickness of the soul, and before the softness of the fibres and the relaxation of the spirit, there are some sort of qualitative a priori that are not yet divided and which latterly impose the same values on both the organic and the spiritual, then it can be understood that there might be sicknesses like madness which from the outset affect both the body and the soul, diseases where the disturbance of the brain is of the same quality, origin, and ultimately nature as the disturbance of the soul.