Nothing is certain but there are facts! Isn't it the case you are the one saying in so many words: " nothing can exist without a beginning".Quote from CaptainObvious:
Surely, you can't be that sure of yourself. Couldn't be is a consideration, but we haven't found anything to be certain as yet.
Mysteries should not be explained away with supernatural explanations, nor should theories be taken at face value just because they're proclaimed by someone with a PHD. There are those of us which are truely interested in finding facts, wherever they may lead, and then there are those which are so in love with their own ideas that the truth is the last thing they want to look for. Both camps are full of the later. Which are you?
May I ask, what sort of certainty do you assign to that ?
But seeing you did ask, I'd say I'm in the camp that cannot imagine even finding any facts by ignoring the obvious, by relying on another fact that the universe is mysterious. I find that's often used as a throw away easy answer excusing everything as mystifying, even when something is actually shown to be certain .
I take nothing on face value when faced with an opportunity to learn facts.