bility and the theory of averages, so well set forth by Laplace, J. Fourier, Ad. Quetelet, Cournot, and others, will always be the best preparation for the positive conception of the social order. While the variable accidental causes or conditions neutralize each other by repetition, the constant conditions (also variable) act with an intensity more and more pronounced. Besides, constancy and necessity are relative rather than absolute ideas, except in the abstract sciences, in which the relative aspect remains understood. From the concrete point of view, the physical environment is the most constant; the organic environment is constant to a less extent; the social environment shares the conditions of both the physical and the organic environments.
I shall not essay in this part of my Introduction, any more than in the preceding parts, to set forth a complete theory, a system. It is still necessary for us to limit ourselves for a long time to perfecting methods, tracing outlines, and indicating directions. My entire sociology is derived from observation of the facts and from the social experiences of history; it is therefore subject to constant criticism and revision.
The true scientific unity, the unity that is sufficient even in theory, is the unity of the positive method; it is with the help of this method alone that I attempt to trace some of the principal outlines of a general, abstract theology. Therefore, the present problem is not that of imagining and sketching a plan for the best of republics, or even that of indicating practical reforms to be realized in modern societies. The Republic and the Laws of Plato cannot serve as models for us. I propose simply to investigate how every society is made, constructed, or rather organized, and what are the constant conditions of its equilibrium and structure. Science and art are distinct; biology and anatomy are not medicine and surgery, that is to say, therapeutics; nevertheless, social science, like all the other sciences, seeks even among the extreme collective perturbations for the confirmation of the necessary and constant order of human aggregates.
Nevertheless, the first result of an exact conception of the
