36 THE WORLD AS IDEA.
matter is merely the modification of the knowing subject, as its idea. Yet the aim and ideal of all natural science is at bottom a consistent materialism. The recognition here of the obvious impossibility of such a system establishes another truth which will appear in the course of our exposition, the truth that all science properly so called, by which I understand systematic knowledge under the guidance of the principle of sufficient reason, can never reach its final goal, nor give a complete and adequate explanation: for it is not concerned with the inmost nature of the world, it cannot get beyond the idea; indeed, it really teaches nothing more than the relation of one idea to another.
Every science must start from two principal data. One of these is always the principle of sufficient reason in some form or another, as organon; the other is its special object as problem. Thus, for example, geometry has space as problem, and the ground of existence in space as organon. Arithmetic has time as problem, and the ground of existence in time as organon. Logic has the combination of concepts as such as problem, and the ground of knowledge as organon. History has the past acts of men treated as a whole as problem, and the law of human motives as organon. Natural science has matter as problem, and the law of causality as organon. Its end and aim is therefore, by the guidance of causality, to refer all possible states of matter to other states, and ultimately to one single state ; and again to deduce these states from each other, and ultimately from one single state. Thus two states of matter stand over against each other in natural science as extremes : that state in which matter is furthest from being the immediate object of the subject, and that state in which it is most completely such an immediate object, i.e., the most dead and crude matter, the primary element, as the one extreme, and the human organism as the other. Natural science as chemistry seeks for the first, as physiology for the second.
