The Spirits' Book
Book One - First Causes
Chapter II - General Elements of the Universe
35. Is universal space infinite or limited?
“Infinite. Assume, for a moment, that there are boundaries. What would be beyond them? This perplexes your reason, which tells you that it cannot be otherwise. The same is true with regard to infinity in all things. The idea of infinity cannot be grasped in your narrow world.”
If we imagine a limit to space, no matter how far away this limit may be, reason dictates that there must always be something beyond it until we arrive at the idea of infinity because this something, even if only an absolute void, would still be space.