" The zombie looks like a man, walks like a man, eats and otherwise functions fully, yet is devoid of the spark. It represents the nagging doubt that lays deep in the heart of even the most zealous believer: behind all of your pretty songs and stained glass, this is what you really are. Shambling meat. Our true fear of the zombie was never that its bite would turn us into one of them. Our fear is that we are already zombies. "

― David Wong , This Book Is Full of Spiders (John Dies at the End, #2)