To begin - the health career model is concerned with space, structures and knowledge (care domains) built around two axes, plus the 'subjects' and 'activities' of health.
How we define and (so) divide space and accord that space salience amid changing contexts is critical to theory, practice and management and the models we subsequently derive:
... The dichotomy does not cut, it defines, it surrounds the closure of a limit, it delineates a boundary. Within the space thus enclosed like meets like. Or rather, conversely, the specific convergance [convenance] or identity, the assembly of the analogous, delimits zones in the disorder which are distinguished from each other. The earth is separated from the waters, air divides from fire. ... p.28.
Michel Serres, (2000) The Birth of Physics, Return of the Model, Turba, turbo. Clinamen Press.