Monad

The Monad or dot-within-a-circle, or circled-dot, is an old symbol supposedly first used by the Pythagoreans to denote the single-source of all things. Even back then, the Monad was immediately associated with the idea of a prime creator, and was counted among the symbols for God. 
The Monad has been used at various times down through history as a symbol of both the Pythagoreans as well as the Order of Infinity. 
-https://en.wikipedia.org/wiki/Monad_%28philosophy%29
Category:God