Wait, this is the version I was looking for:
“Empty space is like a kingdom, and earth and sky are no more than a single individual person in that kingdom. Upon one tree are many fruits, and in one kingdom there are many people. How unreasonable it would be to suppose that, besides the earth and the sky which we can see, there are no other skies and no other earths.” — Teng Mu, a Chinese scholar of the Sung Dynasty (960 — 1280 A.D.)
Beautiful. I never heard that quote before. But it reminds me of Jesus saying “My Father’s house has many rooms; if that were not so, would I have told you that I am going there to prepare a place for you?” (John 14:2)