 Epicurus and the Stoics believe that the principle of bivalence with regard to statements about the future and causal determinism are interentailing: that is, a statement about the future is true if and only if there exists at that time sufficient causal conditions to bring about the state of affairs described in the statement. (Likewise, a statement will be false if and only if there exist sufficient conditions to preclude the state of affairs described in the statement, and neither true nor false if current conditions are sufficient neither to bring about nor to preclude the state of affairs described in the statement.) As the Stoics put it, 