This isn't strictly true... Just because the workings inside the universe seem to run on cause and effect does not mean that the universe was necessarily the result of such. I.e. Is it correct/safe to judge the nature of supernatural (I.e. that which is external to our universe / outside of the nature of the universe) by what happens inside?Premise: The natural universe has a beginning.
If we believe that all things in the natural universe runs off of cause and effect, that means that the origin of the universe would be the effect of some cause.
Some say yes, some say no, others feel that once you get beyond the natural (I.e. Once you talk about "outside the universe" or "before the Big Bang") then such matters are meaningless to us.