The founders of the general systems movement envisaged the development of a theory articulating and inter-relating the principles underlying the systemic behaviours of all kinds of concrete systems. We call this theory GST* (“g-s-t-star”) to disambiguate it from other uses of the term “GST” prevalent in the literature. GST* is still radically underdeveloped, but its nature can be analysed. GST* is a formal theory, because the principles of GST* would apply across all kinds of systems, that is, GST* would predict behaviours and structures of systems qua systems, without regard for the kind of system under consideration, and hence it is neutral with respect to ontology.

There is a long-standing controversy within the systems community about whether a GST* exists in principle, whether it would be of practical value if it did, and how its principles might be discovered. In this chapter we argue by analogy from the history of science that if a GST* could be developed it would be highly valuable, and show that its existence is predicated on the assumption of a philosophical framework called the General Systems Worldview (GSW). We present an argument that development of the General Systems Worldview can guide us to the discovery of general systems principles for a GST*, and that together GST* and the GSW can ground the development of a powerful General Systems Transdiscipline, now called “General Systemology”.