Logic of cause and effect demands that there is a first effect. That effect by definition is best described as the infinite. Which also by definition we can not understand.
All that aside the "proof" stands by itself. Or should I present the other four?
I don't know what you mean. But if men can contemplate an infinite creator, why can they not contemplate an infinite universe? Just because we cannot understand it, does not make it impossible.
"A casual stroll through the lunatic asylum shows that faith does not prove anything." - Friedrich Nietzsche