To my mind Systems Thinking is becoming more and more prevalent and its importance is in fact waning as it becomes ubiquitous. Let us get some perspective on this question to see why this might be the case.
A System is a schema, i.e. a way of understanding things that can be projected on many phenomena. In the Western Worldview there was from the beginning until the last century one schema that ruled all phenomena which was the Form. But at the beginning of the last century two other schemas started to become important which was the System Schema on the one hand and the Pattern Schema on the other. The pattern schema led to a movement called Structuralism. In the last century Structuralism and Systematism both struggled to replace Formalism as the fundamental way of looking at things. Structuralism showed itself invaluable over and over again as the best way to understand phenomena, for instance in the periodic table. In Science structuralism prevailed in disciplines and Systems remained an interdisciplinary topic. However, as an interdisciplinary topic structuralism more or less faded away with the advent of post-structuralism. There are however thinkers who combine the different schemas together into a single framework. Anthony Wilden was one of those thinkers who wrote a book called System and Structure. George Klir developed a systems theory that had structural underpinnings called the Architecture of Systems Problem Solving. This was the precursor to what is now called Complex Adaptive Systems Theory such as that which John Holland laid out in The Hidden Order and the companion book called Emergence. And it is interesting that Complex Systems theory has left behind the General Systems Theory frameworks that were its precursors. Now the problem is not so much seeing things in terms of systems, but instead realizing that each schema has its own usefulness and to give each one its proper due and place within the scientific enterprise. So for instance Forms are associated with proofs as in Geometry, but Systems are related to descriptions, and structures are related to explanations. And what we really need are all of these approaches to understanding in their proper balance.
One of the things I talk about a lot is the relation of the System to its inverse dual, i.e. the OpenScape or what I also call the Meta-system where “meta” means what is beyond the system, i.e. the context, environment, ecosystem, media, etc. Our culture has a hard time recognizing and giving its due to the schema of the meta-system. The meta-system is the realm of indirect indication which also has its place in the ways of understanding phenomena. But we do not realize that the system and meta-system are inverse duals of each other and we tend to be blind to the role of meta-systems and their peculiar organization. So to my mind the next frontier after the system becomes an ubiquitous approach to things, is to be reminded of the role of structure and form, but also to recognize the necessity of considering the meta-systems and their importance. So it is not so much that Systems are important in and of themselves, but more that each schema is important in its own right and to its own degree with respect to explaining different phenomena in specific sciences. All schemas can be applied to any given ontic emergent level of organization found in nature, but different schemas are more appropriate to certain phenomena and others to other phenomena enhancing the various phenomena’s understandability differentially. So my response is that Schemas are important, and different schemas are more important for particular phenomena but all are useful in their own places for different purposes.
It is better if we can combine the schemas and make use of their different strengths in frameworks of Formal Structural Systems for instance that also recognizes the unique organization of the environment as different from that of the System or its structural patterning. In a way Complex Systems has forgotten these advances made by General Systems Theory and needs to relearn that perspective. What is important is to realize that there is not just emergence but also de-emergence is also an important phenomena, and that while systems as gestalts are emergent so to meta-systems are de-emergent, and it is the addition or subtraction of the Gödel Statements that makes something a system as emergent or a meta-system to be de-emergent. And there is an oscillation between emergence and de-emergence in phenomena, not everything is emergent. And what we need to understand is how things oscillate between emergence and de-emergence and how that occurs on the basis of the inverse duality of the system and the meta-system as two different organizational templates for intelligibility of phenomena.
It is fascinating that in our tradition General Schemas Theory, as a theory of all possible schemas was not developed sooner. We need to concentrate on building a good theory of the relations between all possible schemas that play a role in understanding phenomena in Science. The S-prime hypothesis that I developed to kick off General Schemas theory is a beginning. It posits that there are ten schemas and that schemes and dimensions are related to each other. Once we have a theory of Schemas then we can realize the importance of each schema and give each its due. This also allows the System Schema to retain its own value and meaning, because if everything is a system, then system ceases to mean anything and thus loses its intrinsic importance to us as a mode of understanding different from other modes of understanding.
Systems actually derive their importance from their difference from the other schemas that are possible ways of understanding phenomena each with its own contribution to our understanding of things within a scientific framework. The value and importance of the System Schema is not intrinsic to that schema in isolation from the others, but only in as much as we recognize the others and their various values supporting our varied ways of understanding phenomena. The deeper our explanations go the more schemas are involved with respect to any given phenomena, and it is the schemas working together that have the most value for human understanding of natural phenomena.