Despite the importance of systems concepts and the attention that they have received and are receiving, we do not yet have a unified or integrated set (i. e., a system) of such concepts. Different terms are used to refer to the same thing and the same term is used to refer to different things. This state is aggravated by the fact that the literature of systems research is widely dispersed and is therefore difficult to track. Researchers in a wide variety of disciplines and interdisciplines are contributing to the conceptual development of the systems sciences but these contributions are not as interactive and additive as they might be.

As cited in: Journal of systems management. Vol. 25, p. 39. Association for Systems Management, 1974. - Towards a System of Systems Concepts, 1971