Does Bitcoin Repair Itself?

1. Remaking Its Own Parts

The idea. The biologist Robert Rosen described a living system as two processes working together. The first, which he called metabolism, turns raw materials into products. The second makes new catalysts for the first out of those products, so the parts that wear out are replaced from inside. Rosen called the second process repair; Cornish-Bowden and Cárdenas, who wrote the modern account of his work, prefer "replacement", because nothing is mended in the everyday sense. What matters to Rosen is that nothing outside the system has to make its working parts. The site's page on Rosen discusses this test in detail.

Bitcoin against it. Bitcoin's "metabolism" is turning payments into blocks. Its working parts are the miners who build the blocks and the software every copy of the ledger runs. The miners pass the test: when they leave, the new bitcoin each block pays brings in replacements, and nothing outside has to recruit them. The software fails it. Nothing inside Bitcoin writes or fixes its code. When a bug in 2010 let someone create 184 billion bitcoin out of nothing, people outside the protocol had to write the fix within hours.

2. Making and Mending Its Own Boundary

The idea. In 1974 Francisco Varela, Humberto Maturana and Ricardo Uribe proposed that a living thing is a network of processes that produces its own components, including the boundary that separates it from everything else. They called this autopoiesis, self-making, and built a small computer model of a membrane that keeps forming around the chemistry that made it. Barry McMullin later rebuilt that model and showed the membrane breaking and being repaired by the system's own reactions, over and over. The site's Self-Maintaining Membrane runs his version.

Bitcoin against it. Bitcoin's boundary is its rules: a block that breaks them is outside Bitcoin, whoever made it. When two miners win at the same moment the ledger briefly splits in two, and the rule for keeping the longer chain heals the split within minutes. That is a membrane mending itself. But in 2017 a dispute over the rules split the chain permanently, and nothing inside Bitcoin could mend it; Bitcoin Cash went off on its own. The boundary repairs small tears by itself. It cannot repair a tear in the rules that define it, because it did not make those rules.

3. A Loop That Makes More of Itself

The idea. Wim Hordijk and Mike Steel formalised the autocatalytic set: a collection of reactions in which every reaction is sped up by something the collection itself produces, and everything can be built up from a supply of simple raw materials, which they call the food set. Such a set keeps itself going as long as food arrives, and if a member is lost, the others make it again. The site's page on these sets explains the test.

Bitcoin against it. Bitcoin's food set is electricity, computers and people who want to own it, all supplied from outside, which the test allows. The loop is real: the reward recruits miners, the miners secure the ledger, a secure ledger keeps people willing to hold bitcoin, and their demand keeps the reward worth earning. Every member of that loop is produced by the loop except one: the people who maintain the software are not made by the set. They arrive because they can check its mathematics for themselves, which is a real loop of its own, but it runs through human judgment.

4. Regrowing a Target Shape

The idea. Cut a growing organism and many will regrow the missing part. In 1924 Hans Spemann and Hilde Mangold showed that a small region of an embryo organizes the form around it. In 1952 Alan Turing proposed that substances spreading through tissue could set up patterns, and in 1969 Lewis Wolpert described how cells read their position from such a signal and become what that position calls for. The target shape is carried inside the organism, and damage is repaired back toward it. The site's Growth and Repair simulation lets you cut a body plan and watch it regrow.

Bitcoin against it. This is the closest match, and it shows exactly where Bitcoin falls short. Bitcoin also carries target shapes inside it: ten minutes a block, 21 million coins. Damage, such as half the miners vanishing in 2021, is repaired back toward those targets. The difference is where the targets came from. An organism's target shape was produced by its own lineage over millions of years. Bitcoin's targets were typed in by one designer in 2008. The repair runs inside Bitcoin; the blueprint came from outside.

What the Four Tests Agree On

All four tests draw the line in the same place. Bitcoin repairs damage to its operation by itself: lost miners, a slowed pace, a split in the newest block. It does not repair, or produce, its own rules and code. Those came from its designer, and since he left they have been kept by people the system does not pay.

That is why the answer depends on where the line is drawn around Bitcoin. Drawn around the code alone, Bitcoin is an attractlet with excellent self-correction. Drawn around the code together with the people who maintain it and refuse to change its rules, every part is replaced from within, but one of the replacing loops runs through human understanding instead of chemistry or code. None of the four traditions was built to judge that kind of loop. That is the open question, and it may be the most interesting thing Bitcoin has to teach about self-repair.

Sources

Rosen, R. (1991). Life Itself: A Comprehensive Inquiry into the Nature, Origin, and Fabrication of Life. Columbia University Press.
Cornish-Bowden, A., & Cárdenas, M. L. (2022). The essence of life revisited: how theories can shed light on it. Theory in Biosciences, 141, 105–123. doi.org/10.1007/s12064-021-00342-w

Varela, F. J., Maturana, H. R., & Uribe, R. (1974). Autopoiesis: The organization of living systems, its characterization and a model. BioSystems, 5(4), 187–196. doi.org/10.1016/0303-2647(74)90031-8
McMullin, B., & Varela, F. J. (1997). Rediscovering computational autopoiesis. Proceedings of the Fourth European Conference on Artificial Life.
McMullin, B. (2004). Thirty years of computational autopoiesis: a review. Artificial Life, 10(3), 277–295. doi.org/10.1162/1064546041255548

Hordijk, W., & Steel, M. (2004). Detecting autocatalytic, self-sustaining sets in chemical reaction systems. Journal of Theoretical Biology, 227(4), 451–461.
Hordijk, W., & Steel, M. (2018). Autocatalytic networks at the basis of life's origin and organization. Life, 8(4), 62. doi.org/10.3390/life8040062

Spemann, H., & Mangold, H. (1924). Über Induktion von Embryonalanlagen durch Implantation artfremder Organisatoren. Archiv für mikroskopische Anatomie und Entwicklungsmechanik, 100, 599–638.
Turing, A. M. (1952). The chemical basis of morphogenesis. Philosophical Transactions of the Royal Society of London B, 237, 37–72.
Wolpert, L. (1969). Positional information and the spatial pattern of cellular differentiation. Journal of Theoretical Biology, 25(1), 1–47.