Commonly the organism is thought of as a very complicated mechanism whose members and organs mutually depend upon each other. The organism is what the word implies, a tool. But every tool is intended for somebody’s use. Who this one is, is not said, simply because it is considered self-evident. If it be a human organism, it is obviously the man who uses it; if it be an animal organism, it is the animal, and so on. That this is a truth, cannot be denied; but still it expresses only half the truth and scarcely that. Every organic body is used directly by the individuals that form its building material. The human organism is a society of cells, and it is these latter that first of all use the body’s organs for their purposes. But so dominating are the old ideas about the body, that even the cytologists themselves have not been able to shake them off. The cells are continually studied from man’s point of view, but _what man may be from the cell’s point of view is never thought of_. We do not hereby deny all justification to the old conception. The body is also an organ for the soul. The latter, as experience shows, uses the body for its own specific purposes. But this takes place only to a somewhat limited extent. The incomparably larger part of the soul’s work, cares, and endeavors, is devoted to finding means to satisfy bodily wants. But so far as the soul provides for the necessities of the body, it acts as organ for the cells. When man believes that he is running his own errands, he is in reality carrying out the missions of those beings that compose his body. These latter demand for their purposes, if not all, yet at least the largest part of all the work the soul performs in this world. CHAPTER IX. The Fundamental Qualities of an Organism. In order to illustrate the fundamental characteristics of an organic structure in general, we will begin with comparing it with what it most resembles, namely, a complicated mechanism. The likeness is so striking that the very dissimilarities become instructive. First of all we notice the parts of which the machine is composed. What these parts are to the machine the members and organs are to the organism. Every part, like every organ, has a certain duty to perform which it incessantly repeats. The work of the machine is divided among the parts as that of the organism among the organs. As the organ, so the part of the machine can do its share only when in right position and in right order.