—People define the word philosophy differently: My first year of college my philosophy professor defined it as “the rational appropriation of conscious subjectivity.” Would you comment on this definition?”—Joe Cooley 

1) Philosophy consists of the act of REASONING by attempting to produce paradigms (sets of constant relations) of understanding (decidability) in the absence of sufficient measurements (observations) to do so, because of logical(cognitive) and physical(human scale) and technological(mechanical and logical), and economic (cost) limitations. For this reason, all disciplines started as branches of philosophy until they evolved into sciences (measurements) consisting of constant relations in paradigms(networks).

2) We create WISDOM LITERATURES using Mythology(supernormal), Literature (fiction), History, Science, Mathematics, and produce at least the following by conflation:
( a ) Religion: (Emotional) false history, fictional literature, pseudoscience, occult, and fictional law (fictions)
( b ) Philosophy: (Verbal) Sophisms (arguments)
( c ) Pseudoscience and Practical Knowledge (utilities):
Note the Physical>Emotional>Intellectual(verbal) scope of those literatures, and the fictional means we have created to claim pretense of knowledge using them.

3) While Aristotle began with a hierarchy of categories by which to divide knowledge – the categories of philosophy we still used – he lacked knowledge of how to do better than he did. Today we can include metaphysics(grammars), psychology(aesthetics), sociology(ethics), the sciences(epistemology), testimony(speech), law(cooperation), economics(production), politics(commons), group strategy(competition/evolution).
Note that Socrates practiced Criticism(Critique), Plato practiced Justification(Pilpul), only Aristotle Practiced Testimony (due diligence against ignorance, error, bias, and deceit).

4) As far as I know I’ve completed Testimony (epistemology) by converting it to a science (truth) – although we must wait a few decades to see if I’m correct (its very very unlikely that I err). That means that all measurement (“Truth”) is now a question of the sciences. That means that philosophy now consists of the study of CHOICE. Not the true, but the MEANINGFUL, PREFERABLE and the GOOD.

5) Until we solved the problem of epistemology, we lack a most parsimonious paradigm (truth) – meaning a set of constant relations across the entire spectrum of knowledge from the physical, to the emotional to the intellectual, and could not separate philosophy into truth, good, preference, and meaning. There is only one most parsimonious paradigm (truth) but there are an infinite number of paradigms that provide us understanding(meaning), preference(choice), and good (collective).

So the domain of philosophy is at present – if not always – the use of fragmentary information in kaleidic (unpredictable) time, to reason out paradigms (networks of constant relations) that help us understand (Meaningful), how to choose how to achieve the Preferable and the Good.

As such philosophy, as meaning, preference, and good, like creativity, will never end.