Causality, Where does it end?

Lets think of an existence that itself is the cause for it's own existence, I think this existence is fundamentally different from the existence of life or matter.
Probably what we are looking for is something like a singulaity of reasoning, a break point of causality. Something that defines itself without the need of anything else whatsoever. It's the supreme state of self containtment. something like a god, may be?
Whatever it is, it must end the cascade of why. One must be utterly satisfied with that entity with any other need whatsoever, again seems like god?
Something that not only is sufficient for itself but responsible for the beginning of a chain of reasoning, sounds like a creator..hmm.
A self contained, self sufficient, completely free and powerful being - sounds too much like a god, my goodness, that's amazing.