I do see what you mean, and nearly everyone I’ve talked to has had that response, but remember that Lewis didn’t actually believe that that was going to happen. He was only using it as a literary device, and it was only an eternal reflection of choices that were made in a temporal setting. Towards the beginning of chapter 14, he asked MacDonald, “These conversations between the Spirits and the Ghosts– were they only the mimicry of choices that had really been made long ago?” And MacDonald responded, “Or might ye not as well say, anticipations of a choice to be made at the end of all things? But ye’d be better to say neither. Ye saw the choices a bit more clearly than ye could see them on Earth: the lens was clearer.”