Monks preserving scientific knowledge after a nuclear holocaust. Feels a bit dated now, like most SF from the 50's and 60's, especially the idea that humanity is doomed to a repeating cycle of nuclear near-annihilation. I'm skeptical that several thousand years after a nuclear war there would still be a recognizable Catholic Church that appears to have changed less than the actual Church has over the last couple thousand years. Nitpicks aside, it's an interesting read, though it's definitely on the soft side of the SF scale. The last of the three chapters is my favorite (semi-spoilery). With the destruction of civilization by nuclear war again imminent, Miller focuses the story on a bitter dispute between the Abbot and a doctor working with relief crews over the assisted suicide of victims of the first strike. he does a good job drawing the reader into the conflict, even though it doesn't matter in the least, since everyone will be dead in a few days.