This paper suggests that two reasons for the lack of progress toward a widely recognized consensus on a candidate general theory of systems (GST as GTS) are: (1) there does not exist a consensus set of criteria with which to judge alternative candidates (so they just continue to proliferate without any unification); and (2) there is little or no tradition of judgement or selective force in the ISSS eliminating alternatives or forcing them to integrate. In this presentation and paper, a list of 15 criteria or features that we propose MUST be present in any candidate GTS are submitted, described and critiqued. One major criterium is that any candidate GTS must cite or utilize multiple (as in many) isomorphies as hypothesized by the Founders of GST in the beginning. The author knows of several authors of alternative systems theories who dispute this claim and so arguments for and against are presented and refuted. Then the list of criteria for a GST are compared with a list of twenty Tenets (or features) of the Systems Processes Theory (SPT). Each tenet is explained in terms of the criteria needed for a GST. Then a listing of a dozen other candidate systems theories are listed, examined, and discussed. Some of these theories of system dynamics are adequate for the purposes or functions for which they were designed, but this presentation will show that they are not within the realm of the science of systems intended by the ISSS Founders or are not, in fact, general. SPT will be shown to be strictly a science of systems as opposed to attempts at systems thinking for purely human design objectives. SPT will also be shown to be general in the widest definition of that term. Then the SPT will be compared with newer descriptions of features needed for a GST emerging from the work of Rousseau and Wilby et. al. and the BCSSS (Bertalanffy Center for the Study of Systems Science). Several continuing obstacles that inhibit formation of a consensus on a unified GST will also be considered and their history discussed as well as the current fate and/or status of the SPT.
