The intuitive strength of the argument stems from the general assumption that backward causation presupposes an ontologically closed future—a metaphysical position about time usually named eternalism. Hence it is not an argument only against backward causation but against eternalism as well. Suppose it is now already true or false what is going to happen tomorrow; then there must be some future truth-makers that determine that it is now already true or false what is going to happen. The conseque