In response to William Lane Craig’s assertion that tigers don’t just pop into existence and neither should the universe, Wes Morriston notes that “We have no experience of the origin of worlds to tell us that worlds don’t come into existence like that…That is why the absurdity of tigers and the like popping into existence out of nowhere tells us nothing about the utterly unique case of the Beginning of the whole natural order”. (p. 84)
What Morriston doesn’t understand is that when Craig is referring to tigers, he’s also referring to anything. It is a universal maxim that ex nihilo, nihil fit, from nothing, nothing comes. It doesn’t matter if we’re using tigers or universes as examples. Matter just doesn’t happen from nothing, Casimir effect included.