In the chemical natural process we observe the most varied elements related to each other in the most various ways. They attract or repulse each other. They enter into combinations or they withdraw from them. These are nothing but actions and interactions which we ascribe to certain forces inherent in these elements.
The vegetable and animal natural process begins, at any rate, with the contact of heterogeneous elements which we characterize as sexual cells (gametes). They exert upon each other a reciprocal influence which sets into activity the vegetable and animal process.
The extent to which science is permeated by the hypothesis that heterogeneous elements reacting upon each other are necessary to a natural process is best indicated by the atomic theory.
Obviously, it is conceded that the origins of all natural processes cannot better be explained than by the assumption of the existence in bodies of invisible particles, each of which has some sort of separate existence and reacts upon the others.
The entire hypothesis is only the consequence of the concept of a natural process which the observation of nature has produced in the human mind.
Even though we conceive the social process as characteristic and different from the four types of natural processes mentioned above, still there must be identified in it the two essential factors which constitute the generic conception of the natural process. And this is, in fact, what we find. The numberless human groups, which we assume as the earliest beginnings of human existence, constitute the great variety of heterogeneous ethnic elements. These have decreased with the decrease in the number of hordes and tribes. From the foregoing explanation we are bound to assume as certain that in this field we are concerned with ethnically different and heterogeneous elements.
The question now remains as to the second constitutive element of a natural process, namely, the definite interaction of these elements, and especially as to those interactions which are characterized by regularity and permanency. Of course, we must avoid analogy with the reciprocal interaction of heterogeneous elements in the domain of other natural processes. In strict conformity with the scientific method we take into consideration merely such interactions as the facts of common knowledge and actual experience offer us. Thus will we be able, happily, to formulate a principle of the reciprocal interaction of heterogeneous ethnic, or, if you will, social elements, the mathematical certainty and universality of which cannot be denied irrefutably, since it manifests itself ever and everywhere in the field of history and the living present.
This principle may be very simply stated: Every stronger ethnic or social group strives to subjugate and make serviceable to its purposes every weaker element which exists or may come within the field of its influence. This thesis of the relation of heterogeneous ethnic and social elements to each other, with all the consequences proceeding from it, contains within it the key to the solution of the entire riddle of the natural process of human history. We shall see this thesis illustrated ever and everywhere in the past and the present in the interrelations of heterogeneous ethnic and social elements and become convinced of its universal validity. In this latter relation it does not correspond at all to such natural laws, as, for example, attraction and gravitation or chemical affinity, or to the laws of vegetable and animal life. In order better to conceive of this social natural law in its general validity, we must study it in its different consequences and in the various forms which it assumes according to circumstances and conditions.