[Mr Ramsbotham]

Heaven knows I’m no physicist, but I’d be willing to make a gentleman’s wager that there is only one substance in the universe, everything arises from it, and the universe is filled with it. And God is apart from it.

[Boogieman]

Yes, there is one substance that fills the entire universe: space. There is a theory that is based on the idea that all matter and energy arises from waves in that space:

Wave Structure of Matter - The Most Simple Theory of Reality

[who_would_fardels_bear]

"that there is only one substance in the universe, everything arises from it"

...or there might not be any substance at all, just bundles of properties...

Substance