Yep...I edited...is that 'more specific'?
This 'at least one other thing' had to have come from OUTSIDE of the known physical universe in order to have created the initial reaction. If it was merely a spontaneous mystical happening then such happenings would be evident throughout nature...they are not. All happenings can be sourced to reactions. Every other thing that has happened INCLUDING the Big Bang has been and is a REACTION to the initial action.