If There Was 100 percent certainty in the Universe we would not need probabilty.

If There was 100 percent certainty in the Universe we would not need probability. Maybe there is 100 percent certainty?    Probability is an interesting concept which seems to pertain to assaying the future rather than analyzing the past. It is pretty clear that if we know what happened in the past everything that happened was 100 percent certain so long as memory is good.  What is the probability of getting 4 Aces in a poker hand verses what was the probability of having that exact hand in a particular hand?  It was 100 percent certain because the event occurred.  Probability of that 4 aces card hand is not possible to change after the event occurs.  You can speculate about other possibilities that never happened . Yes the odds would be what future probability would be except all the hands of cards ever dealt are now history and cannot be changed.  There fore the past is at least theoretically 100% certain even if we don't have a clear memory of all of it or any of it.    The future is completely speculative and that is where probability seems to become most useful.  Probability allows us to predict future outcomes at least to some degree.  If this becomes a principle of physics then if we look back in space and time with astronomy then the probability of any of it is irrelevant.