The Repugnant Conclusion is a controversial theorem about population size. It states that a sufficiently large population of lives that are barely worth living is better than a smaller population of high quality lives. This is highly counter-intuitive. It implies that we can improve the world by trading quality of life for quantity of lives. Can it be defended?

Christopher Cowie explores these questions and unpacks the controversies surrounding the Repugnant Conclusion. He focuses on whether the truth of the Repugnant Conclusion turns - as some have claimed - on the...