 In proposing a principle of “just savings” Rawls never discusses the non-identity-problem and for most of his discussions (but see Rawls rev. edition 1999: 141) he assumes that the number of future people is constant (for criticism see Heyd 1992: 47; Dasgupta 1994; Casal &amp; Williams 1995; Barry 1999: 107–111; Gosseries 2001: 330–333). However, his principle of just savings can be understood to provide us with a substantive understanding of intergenerational sufficientarianism. It can be understood as an interpretation of a threshold notion of harm in different number choices (see Reiman 2007; Attas 2009).