ABSTRACT
The raw material of social systems is the history of mankind. The record of history, however, is no more than raw material. In order to have knowledge of social systems, we must abstract out of the almost infinite complexity of this record those elements which exhibit enough regularity to be subject to analysis. Social systems, that is, are essentially abstractions from reality; without these abstractions, however, we cannot hope to understand reality. A system is anything that is not chaos, and even though history seems highly chaotic at times, we have an intuitive feeling that it is not pure chaos. If it is not chaos, there is system in it, and if there is system in it, there is some hope that the system may be perceived and understood.
