 According to such a threshold notion of harm an action harms a person only if, as a consequence of that action, the (then existing) person falls below a normatively defined threshold (see McMahan 1998: 223–229; Shiffrin 1999). This threshold notion is unaffected by the non-identity-problem, for here the finding of harm does not require that the person who is in the sub-threshold state would be in a better state in the situation that would have obtained in the absence of the harming action. Thus, future people can be said to be harmed by currently living people’s actions even if these actions are among the necessary conditions of the existence, identity or number of future people. Such a notion of harm limits the practical significance of the non-identity-problem to different degrees depending upon how the threshold is substantially defined (see  §4  below).