It doesn't make sense when the evidence tells us the universe can't come from nothing nor always have existed to then ask what caused the uncreated. What you are actually doing is you have gone to Step 4 of the 4 Step Proof for God that deals with the alleged supernatural cause and effects for an eternity of the past. Yet if there was an eternity of the past of cause and effects outside the natural realm, mankind would have approximated into that alleged past eternity and not still be sinning to the extent we still do along the exponential progression of conscience we are clearly on.