I was now about to form another being of whose dispositions I was alike ignorant; she might become ten thousand times more malignant than her mate and delight, for its own sake, in murder and wretchedness.
No one knows what someone will be like after they've been brought into the world, but we don't lament every single person who is born. When someone you know is having a kid you don't say to them: "remember H.H. Holmes? Are you sure you want to have kid? They might be ten thousand times worse than H.H. Holmes!" Because that would be ridiculous.