Cultural evolution is an interdisciplinary, rapidly developing, scientific framework aiming to provide a naturalistic and quantitative explanation of culture. Tim Lewens’s Cultural Evolution is, to my knowledge, the first book-length philosophical review of the theoretical background of the field. The analogy between biological and cultural evolution is as old as the idea of biological evolution itself, and it has been—and is—prone to several sorts of misunderstandings and loose implementations. For this reason, the first two chapters of Lewens’s book are a timely, and efficacious, attempt to clarify the constraints that an approach to culture needs to satisfy in order to be genuinely “evolutionary.