Closed Loop Systems

There is a fiercely rigorous definition. In a closed-loop (aka “closed”) system, Kenneth Boulding explains,

There are no inputs from outside and no outputs to the outside; indeed, there is no outside at all. Closed systems, in fact, are very rare in human experience, in fact almost by definition unknowable, for if there are genuinely closed systems around us, we have no way of getting information into them or out of them; and hence if they are really closed, we would be quite unaware of their existence. We can only find out about a closed system if we participate in it. Some isolated primitive societies may have approximated to this, but even these had to take inputs from the environment and give outputs to it. All living organisms, including man himself, are open systems.C136

And there is a more relaxed understanding where the system is “closed” only with respect to materials, while allowing energy and information in and out. But even that has problems. Living systems produce waste which, unless released to another system, would become toxic and destroy them; or, to see it from another point of view, every activity involves some disordering and dissipation, along with losses of materials, and it is only outside systems—that is, systems working to different rules—that can do the necessary re-ordering and re-supply. So, unless we think of a material exchange system on a vast scale such as that of the planet, there is no such thing as a closed-loop system. Tim Jackson writes,

The concept of a “no waste economy” is just an illusion. No such thing can exist.C137

So we have to be content with a pragmatic view which looks to the benefits of a system being “roughly” closed—being substantially self-sufficient because it recycles most of what it uses.

And here a further source of vagueness comes in: it is impossible to be exact as to which closed-loop system we are talking about. For every large system, there are many holons (smaller systems, subsystems or subassemblies) within it, and even smaller ones within these. Yes, a degree of self-sufficiency applies at every level in this hierarchy, but if the hierarchy as a whole is to work this is largely due—especially at the lower levels—to the exchanges and interdependences. That is, exchange and self-sufficiency are complementary, with interdependence becoming weaker—systems becoming more realistically closed—at the higher levels.C138

If that nuanced structure degrades—if it blows up to an enormous size and loses its harmonic order—the default position it will triumphantly but briefly enjoy will be a through-and-through open system, importing orderly materials (i.e., materials with low entropy), and then dissipating them.

So the property that a resilient system looks for is not the elimination of openness, but limits to it: it uses the exchange and recycling of surpluses and wastes at lower levels as enabling conditions by which higher levels can achieve greater degrees of self-reliance.

Closed-loop systems in Lean Logic, then, are systems or communities that have worked out how, collectively, to reuse most of their materials. For a natural ecology, this is routine, a necessary condition for its existence; in an open system such as a market economy, this condition is absent. For a community intent on a degree of eco-independence, the closed-loop system is a necessity; in a sense the definition of what it is aiming to do. To maintain a closed-loop system, it will need to establish and conserve the small-scale, attuning to the elegance of not needing a vast infrastructure of regrettable necessities. It will conserve its foundation capital in the form of fertile soils, a conserved genetic and cultural endowment and a protected climate, and it will limit access and scale to levels which will not lead relentlessly to that foundation capital being destroyed.

Closed-loop systems are, at best, an approximation. The principle does, however, provide the central, elementary principle by which the burnout, dissipation, and entropy of the human ecology could, perhaps for the long term, be delayed.

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David Fleming
Dr David Fleming (2 January 1940 – 29 November 2010) was an economist, historian and writer, based in London. He was among the first to reveal the possibility of peak oil's approach and invented the influential TEQs scheme, designed to address this and climate change. He was also a significant figure in the development of the UK Green Party, the Transition Towns movement and the New Economics Foundation, as well as a Chairman of the Soil Association. His wide-ranging independent analysis culminated in two critically acclaimed books, Lean Logic and Surviving the Future. A film about his perspective and legacy - The Sequel: What Will Follow Our Troubled Civilisation? - was released in 2019, directed by BAFTA-winning director Peter Armstrong. For more information, including on Lean Logic, click the little globe below!

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