 We might want to understand the threshold as an element of an egalitarian understanding of intergenerational justice. Egalitarian reasons allow us to object to inequalities, for egalitarian reasons make it possible for us to understand relative differences between the states of persons as something “which is itself to be eliminated or reduced” (Scanlon 2005: 6). We might hold that the standing of people relative to their contemporaries is (extrinsically or intrinsically) important (see the entry on  equality)  and that the threshold notion of harm ought to reflect, say, the average level of well-being that people realize—or that future people will realize: the higher the average level of well-being, the higher the threshold level of harm should be set.