You have thrown me a real curve ball which I cannot reconcile.
"All is one" is a term associated with Buddhist and Hindu thought. But to speak of a single, unified world system does not imply that "All is one" in the Hindu or Buddhist sense.
A single unified world system can easily be imagined as the outcome of Big Bang/inflationary universe theory — which clearly indicates that the universe had a Beginning (origin). That is, is not an "eternal universe." Nor do pantheist thinkers have available to them any logical tools to analyze and elucidate what they mean by "All is one" — for there is nothing in a pantheistic system that can serve as a basis for logic and logical analysis.
Pantheist systems make God coextensive with phenomenal reality and embed Him IN IT. The Judeo-Christian tradition does NOT conflate the Creator and the Creation in this way. The divine Logos is not "IN" the world system, although the world system expresses it. Just as Michelangelo is not "IN" his magnificent sculpture of "David," nor in any of its composing materials. But there would not be any "David" without Michelangelo!!!
Indeed, it seems to me pantheistic systems represent flights from reason and logic into the dissolution of human thinking and ultimately of personality in the "desired" state of Nirvana — a condition of utter, forgetful nothingness whose goal is to relieve us of the pain and suffering of human existence by relieving us of our personal identity and individuality.
No wonder science did not arise in the East, but only in the West....
Anyhoot, I am not a "Gaia" fan. That was Lovelock. Interesting; but finally unpersuasive. Lovelock's work was "earthbound." In that sense, he was not looking for ultimate principles....
And certainly I am not a New Ager! What a pail of useless bilgewater!!! Trust me on this one; I know this from personal experience.... :^)