Fred Hirsch's book "Social Limits to Growth" contains a very interesting exploration of the nature of positional goods, including personal time. One relevant as

Fred Hirsch's book "Social Limits to Growth" contains a very interesting exploration of the nature of positional goods, including personal time. One relevant aspect is that as material productivity increases, the relative prices of positional goods increase, because their supply remains limited. It is quite an unsettling read, and I highly recommend it.