Soul is, therefore, according to our definition, equivalent to animal life, in contrast to the life of the plant. The significance of the distinction lies in the intermediation of the general organic unity, not in a qualitative division. The elements are the same; only their connection is different, and that which distinguishes the animal is a centralization of the organs. In referring to the possession of soul by the animal, we simply point out the independent manner in which, by reason of sensation, its impulses govern, and develop, through the scale, up to consciousness and will. Of course the gradations are very numerous, inasmuch as the functions of the soul are determined by the development of the organism. The difference between animals whose sensation attains clear consciousness and such as do not attain to more than a mechanical action, does not concern us, as long as we regard the psychical phenomena in their most general form. Every animal possesses soul; we avoid the expression "_a_ soul," as giving the soul the significance of something by itself. In like manner, we do not say that _a_ life, but that life belongs to the animal. The chief condition necessary to soul as to life consists in union to a whole, and soul represents the gradation by which life lifts itself to the plane where it becomes a mirror of the world. Sensation, as centralized in the brain, becomes perception, the sensation of a part becoming the sensation of the whole, a _feeling_ of the individual. It is perceptions which cause movement. To find a connection between perception as generally understood and the action of the muscle would be as difficult as to show the connection between body and soul in the sense of Spirit. But if we regard perception as feeling, then the awakening of a corresponding impulse, and the transformation of this into will, which finds expression in a corresponding motion, is something so natural that it needs but a glance at the nerve-apparatus in order to comprehend the rapidity of the whole process. With regard to the unconscious character of the greater part of the process, and its corresponding rapidity, we have to consider the gradual nature of the development of the nervous system, the gradual drill of the parts, until the whole process becomes perfect. By feeling is here not meant necessarily feeling as pain or pleasure. This quality of feeling does not necessarily belong to every perception, else thought, as a train of perceptions, would be unbearable; a certain strength of feeling is necessary in order that it may attain the character of pain or pleasure; as we recognize a boundary at which sensation begins, so we recognize one at which feeling begins to attain the character of pleasure and from which, up to a second boundary-line, it continues to appear as pleasure; beyond this line it appears as pain. Moderate feeling is beneficial to the organism, immoderate feeling harmful; hence the appearance of the