The steady state economy is an entirely physical idea. Any non-physical the different parts of an economy may grow indefinitely. Even so the physical components (e. g. supplies of organic resources, human populations, and stocks of human-built capital) tend to be constrained and endogenously granted. An economy could reach a steady state after a period of growth or after a period of downsizing or perhaps degrowth. The objective should be to establish it at the sustainable scale that doesn’t exceed ecological boundaries.