If that were true, why has no documented civilization or precivilization existed without an element of spirituality or religion in their history?
The point is Spirituality came first, and based on evidence, was needed for humans to form groups larger than a small family unit as a way to unify "morals".
"What if we had science instead" is a moot point because we have Science now and proved early humans wrong.
I sincerely do not believe you understand English well enough to understand what I am saying, and I do not have the ability to explain it any better than I already have.
If you are hung up on the whole "God" thing, know it isn't about that.