This brief and simplified discernment is to complement diverse past discernments on epistemology and ontology:
Even in traditions that the self exists. And exists beyond the physical body. Exists only as epistemology rather than ontology. However, this should point to obvious contradiction of principle or fundamental nature of existence, life and existence are both epistemology and ontology. And therefore, epistemology implies ontology and ontology implies epistemology. In other words, they are irreplaceable and irreducible.
Simplified life and existence to epistemology simplified the lack of knowledge, sciences, and practices. And even when the philosophy emphasized separated self, the separated self is still stream of formless or consciousness rather than form-formless or body-mind. And give rise to easy explanation on life and existence as well as bias social constructs such as incarnation, re-incarnation, hierarchy, and patriarchy:
1.0 For incarnation and re-incarnation to be rational, consciousness and mind has to be formless or existed as stream of consciousness rather than as form-formless or body-mind (whether in material or immaterial worlds). Incarnation explained through the essence of nature (i.e. essence of nature are everywhere and in very thing. Consciousness is everywhere but not in everything) and process of being and becoming rather than individual entity or supernatural would be scientific.
2.0 To ease the explanation or construct of re-incarnation in all kind of realms and worlds or re-born as all kind of species
3.0 Become god or the whole rather than part of the whole. Being part of sum of parts of the whole is different from being the whole. And which even endowed or embodied with infinite potentialities of possibilities facilitating (i.e. through the universal intertwinement and entanglement with the local and non-local cosmos or the greater whole) by the greater whole is still different from the greater whole. And for an individual to be rationalized as the whole, the physical body (whether material or immaterial) can no longer exist or consciousness can only be stream of the whole consciousness.
4.0 Formless can still explain stream of consciousness as continuous. Otherwise, with form-formless. how does the immaterial physical body (i.e. has to die. And which would require process and mechanism far more complex than teleportation of species. And teleportation of an individual which is stuff of fiction. And therefore, the nature or existence of the subtle body-mind of the many sentient composite body-mind system) dissolve to re-incarnate. And all the while maintain continuous stream of consciousness and mind.
5.0 To ease the explanation of eternal life through stream of consciousness of the whole rather than as factual parts of sum of parts of the greater whole.
While traditions that believe in form-formless, have much difficulties comprehending and reconciling with such as interdependent and interconnectedness of life and existence, dependent and interdependent origination, dependent and interdependent arising, being as fractal parts of sum of parts of the greater whole, process of being and becoming, intertwinement and entanglement in and with the local and non-local cosmos, evolution and emergence, and the whole is far greater than sum of it parts.
Just as existence in the known physical world requires form-formless, existence beyond the known physical world would also required form-formless. While formless would no longer be considered as self existence. But rather, potentially as epistemology of others' ontology or existence within other entities rather than self existence. The philosophy and science of epistemology and ontology is clear and obvious or unmistakable, self existence required form-formless such as existence in the known physical world requires form-formless or body-mind (i.e. mind belongs to subtle body-mind). And existence beyond the known material world or in the immaterial world implies or guaranteed form-formless.
Epistemology of Life and Ontology of Existence Foundation and Institute