Ah, philosophy!
So precious little of it around these days.
Thank you, Andrew, for this thread.
We are all philosophers and metaphysicians, but many of us in an inchoate, even unconscious way.
It is usually accepted that western philosophy more or less starts with Plato (although many earlier Greek thinkers are also significant). And who does Plato most quote and argue with in the Dialogues? A poet.
"Homer is by far the most quoted author in the dialoges: of the 296 quotations listed by L Brandwood in his "Word Index to Plato" for the 28 dialogues I include in my tetralogies, 131 come from Homer, 93 of which come from the Iliad, and 38 come from the Odyssey (explicit quotations as well as obviously homeric expressions); far behind, we find, aside from Protagoras whose statement on "man-measure" is quoted or alluded to 19 times, Hesiod and Euripides, with 16 quotations each, then Pindar, with 13 quotations and Aeschylus with 12 quotations; the remaining quotations come from a multitude of known and unknown authors, only a few of whom are quoted more than once. Aside from explicit quotations and use of homeric expressions, the name of Homer appears 164 times in the dialogues."
http://plato-dialogues.org/biblio.htm
And so one could argue that, since Plato builds his philosophical system on and around Homer, western philosophy begins with poetry.
Somewhere along the way, poetry and philosophy parted company, but I think they belong together.