We may summarize these considerations as follows.

Similar general conceptions and viewpoints have evolved in various disciplines of modern science. While in the past, science tried to explain observable phenomena by reducing them to an interplay of elementary units investigatable independently of each other, conceptions appear in contemporary science that are concerned with what is somewhat vaguely termed “wholeness,” i.e., problems of organization, phenomena not resolvable into local events, dynamic interactions manifest in the difference of behavior of parts when isolated or in a higher configuration, etc.; in short, “systems” of various orders not understandable by investigation of their respective parts in isolation. Conceptions and problems of this nature have appeared in all branches of science, irrespective of whether inanimate things, living organisms, or social phenomena are the object of study. This correspondence is the more striking because the developments in the individual sciences were mutually independent, largely unaware of each other, and based upon different facts and contradicting philosophies. They indicate a general change in scientific attitude and conceptions.

Not only are general aspects and viewpoints alike in different sciences; frequently we find formally identical or isomorphic laws in different fields. In many cases, isomorphic laws hold for certain classes or subclasses of “systems,” irrespective of the nature of the entities involved. There appear to exist general system laws which apply to any system of a certain type, irrespective of the particular properties of the system and of the elements involved.

These considerations lead to the postulate of a new scientific discipline which we call general system theory. Its subject matter is formulation of principles that are valid for “systems” in general, whatever the nature of their component elements and the relations or “forces” between them.

General system theory, therefore, is a general science of “whole- ness” which up till now was considered a vague, hazy, and semi- metaphysical concept. In elaborate form it would be a logico- mathematical discipline, in itself purely formal but applicable to the various empirical sciences. For sciences concerned with “organized wholes,” it would be of similar significance to that which probability theory has for sciences concerned with “chance events”; the latter, too, is a formal mathematical discipline which can be applied to most diverse fields, such as thermodynamics, biological and medical experimentation, genetics, life insurance statistics, etc.

This indicates major aims of general system theory:

- There is a general tendency towards integration in the various sciences, natural and social.
- Such integration seems to be centered in a general theory of systems.
- Such theory may be an important means for aiming at exact theory in the nonphysical fields of science.
- Developing unifying principles running “vertically” through the universe of the individual sciences, this theory brings us nearer to the goal of the unity of science.
- This can lead to a much-needed integration in scientific education.

A remark as to the delimitation of the theory here discussed seems to be appropriate. The term and program of a general system theory was introduced by the present author a number of years ago. It has turned out, however, that quite a large number of workers in various fields had been led to similar conclusions and ways of approach. It is suggested, therefore, to maintain this name which is now coming into general use, be it only as a convenient label.

It looks, at first, as if the definition of systems as “sets of elements standing in interaction” is so general and vague that not much can be learned from it. This, however, is not true. For example, systems can be defined by certain families of differential equations and if, in the usual way of mathematical reasoning, more specified conditions are introduced, many important properties can be found of systems in general and more special cases (cf. Chapter 3).

The mathematical approach followed in general system theory is not the only possible or most general one. There are a number of related modern approaches, such as information theory, cybernetics, game, decision, and net theories, stochastic models, operations research, to mention only the most important ones. However, the fact that differential equations cover extensive fields in the physical, biological, economical, and probably also the behavioral sciences, makes them a suitable access to the study of generalized systems.

I am now going to illustrate general system theory by way of some examples.

Source: Bertalanffy Ludwig Von (1969), *General System Theory: Foundations, Development, Applications*, George Braziller Inc.; Revised edition.