There is utility, comfort and conciseness in word definitions. For many of the SPs there are many definitions by different authors in the literature. By assembling large numbers of these definitions and comparing them one can see repeated use of the same phrases. This side-by-side juxtaposition is instructive in itself. By collecting all such phrases one can assemble an uber-definition. The two-volume Encyclopedia of Systems Science attempts to do this. So will SPT.
The Fellows (honorary title, recognition of contributions) of INCOSE (the International Council on Systems Engineering) did this under the leadership of our colleague Hillary Sillitto of the United Kingdom. They did it to try to pin down a consensus definition for the most basic word in the field – the definition of “system” itself. They asked many systems engineers and systems thinkers about their favorite definition for system. What they found was that the worldview of the person answering the questionnaire influenced very markedly the attitudes they possessed for the word “system” and the definition they espoused. They could only collect a lot of definitions; no preferred one pleased all the different worldviews. We expect that this would be the case for many of the definitions for the range of candidate isomorphies. So perhaps the best we can do is collect for study the largest extant set of definitions possible for each.