every phenomenon in this field as the other universal concepts. This is so because a certain magnitude, known to us immediately as mechanical work, may be proved to be a constituent of every physical phenomenon, i. e., of mechanics, physics and chemistry, by virtue of its qualitative transformability, and its quantitative immutability. In other words, it is possible to characterize every physical phenomenon completely by stating what quantities and kinds of energy are present and into what kinds of energy they are transformed. It is, therefore, more rational to term the so-called physical phenomena, energetic.
That such a conception is possible is now generally acknowledged, but its utility is usually doubted. These doubts are at present justified, inasmuch as a complete exposition of the physical sciences from the point of view of energetics has not been thoroughly carried out. If the above-mentioned criterion of a scientific system, viz., the conformity of the representing manifoldness to the one depicted, be applied to this question, we shall find unmistakably that all previous systematizations, which in the form of hypotheses have been attempted in these sciences, are faulty in this respect. Hitherto manifoldnesses have been used for the purpose of 'depicting' experiences the character of which corresponded to the depicted object only in a few main points. No attention was paid to the necessity of exact correspondence. There was no concise formulation or investigation of this side of the problem.
Now the energetic point of view permits as great a certainty in the method of depiction or expression as is necessary or possible for the state of the science at the time. For the manifoldness-character of each department there is a special form of energy. Thus science has long since distinguished between mechanical, electrical, thermal, chemical and other forms of energy. All these different varieties are related through the law of transformation with the conservation of energy. They are therefore organically connected. On the other hand, it has been possible to find the energetic expression for every manifoldness as yet discovered empirically. The future system of energetics in its entirety will therefore be a table of all the possible manifoldnesses of which energy is capable. It must be noted, however, that as a consequence of the law of the conservation of energy, energy is of necessity a positive magnitude which furthermore is without limit additive. Each special kind of energy must therefore also have this character.
The very slight degree of manifoldness which these conditions seem to leave us is increased very much by the fact that every form of energy may be resolved into two factors. The latter are subject to but a single limitation, viz., that their product, energy, fulfils the above conditions, while they themselves are far more free. Thus, one of the factors of a form of energy may become negative instead of positive, if the other factor also becomes negative.
