ABSTRACT
Broadly speaking, time symmetry suggest that we care about the distribution of an individual's income receipts over time, but not about the time sequence of those receipts. This is more than time symmetry implies, however, since a permutation fi swaps all the incomes in two periods s and t, not just X;s with X;1 for a single person i. But even the weaker idea of time symmetry, as stated, is objectionable since we may not be indifferent to the time sequence of incomes as, for instance, between the situation in which incomes are originally different and then become equal, and the time symmetric equivalent structure in which incomes are initially equal, and then become different.
