Steve Kurtz writes: “I agree with most of your post (“The wilful world economy!”), Keith, but the physical universe, and its components have shown no ability to ever reach a steady state. Energetic systems grow and senesce. At least that’s what I understand.”
Highly energetic systems do, of course, grow and then subside, as you say. The fast-moving atoms and molecules always seek to dissipate as much waste heat as possible — and as far away from their source as possible (entropy). But when you talk of physical systems that are constantly driven by new energy from the outside, then there’s no reason why a state of balance should not follow — at least for us humans to describe it as a steady-state.
Indeed, ever since the first replicating molecule of life appeared on earth and was energised by the daily receipt of sunlight then the ecology of the earth developed over billions of years in what is reasonable to describe — from our point of view — as a long series of steady-states from year to year and decade to decade.
Exactly the same applies to industrialised man from the time he discovered vast resources of deep-mined coal adding to the energy able to be added. And this was boosted enormously by the further additions of oil and gas. Economic growth could thus bound forth. But it would reach an inevitable steady-state unless further huge quantities of additional energy could be found and then applied to yield yet more economic growth.
Fortunately that is no longer possible — even with shale gas! — and, with luck, the world’s manufacturing and trading system, may have already reached stasis, and the wild life of the planet given a chance to start recovering.