The Biological Derivation Hypothesis

Friday 26 May 2023

Nick Nielsen
10 min readMay 28, 2023
Samuel Huntington’s map of civilizations on a crowded Earth.

Back in newsletter 170 I wrote about how I had changed my mind on the idea of planetary civilization — previously I had considered our global civilization a de facto planetary civilization lacking only legal and political unification, whereas I had since come to see that Earth now consists of formerly separate civilizations now living cheek-by-jowl with each other, often unhappily — and then in newsletter 176 I introduced the idea of a properly planetary civilization, which, following my previous analysis of civilization, is a civilization that thematizes a planet as its central project.

While the logic of my own concepts drives to me to properly planetary civilization as the preferred formulation, the idea of a de facto planetary civilization has certain applications, so that both are useful, but they need to be distinguished. Following my usage in Indifferently Spacefaring Civilization and Space Development Futures: Spacefaring Infrastructures of Indifferently Spacefaring Civilizations, I should be using “indifferently planetary civilization” for those civilizations that do not take a planet as their central project, but in my notes I have simply called this idea the planetary conception of civilization. Certainly I could improve this terminology. It is worse than pointless — it is misleading — to use confusing terminology (like Heidegger distinguishing between “existentiel” and “existentiell” — if the distinction is sufficiently important to be observed, then it is sufficiently important to make the terminology clearly distinct). But it often takes mulling over matters for some years before one hits on the perfect terminology to intuitively convey concepts that have been defined long before, but remained obscure simply because there has been no intuitive way to express them.

Here a formal calculus is our friend, because we can just introduce further terms, which, once clearly defined, need only be distinguished by the most minimalist notational conventions — for example, Civ1, Civ2, etc., for distinct concepts of civilization. It helps to be able to model a new calculus on some familiar calculus which is homeomorphic to it, so if a derivation works in the one, it will work in the other. With an earlier theory as a template, a formal calculus can be rapidly developed. With civilization, we don’t have this luxury. At least, I know of no formal calculus in the social sciences that suggests itself as a model for a theory of civilization. The very idea of a formal calculus in social theory would probably strike most as outrageously artificial and reductive, like Woodger’s axiomatization of biology.

So let’s set all this aside for the moment and use the admittedly awkward an uninspired terminology such that the “indifferent conception” is the planetary conception of civilization in which the planet in question plays no special role in the central project of the civilization in question, and the “proper conception” is planetary civilization that takes a planet as its central project. The indifferent conception is the presumptive conception of civilization employed in SETI, which often has something to say about civilization, but the concept of civilization has never struck the SETI research community as sufficient important that they should spend any time on working out what exactly it is they are looking for.

A SETI astronomer (or, if we prefer Adam Frank’s terminology, a technosignature scientist) looks for signs of other civilizations (or, again, if you prefer, signs of other technology) at such a great distance that all potential sources of signals are reduced to a point. Even a very “loud” alien civilization would be a mere point… unless some other civilization had established multiple settlements off its homeworld and was transmitting from several of these, and these other settlements were at a sufficient distance that the point source of the signal could be distinguished from some other point source. But in terms of the problems of the indifferent conception, an entire planet is reduced to a single point, so that there is no distinguishing, by means of contemporary SETI technology, different civilizations on a single planet. The planet radiates as one. Of course, we can construct scenarios in which this is not the case. Perhaps a single planet radiates in two very different frequency bands, or two distinct classes of singles are distinguishable due to their encoding. Much as we can distinguish amplitude modulation and frequency modulation in terrestrial radio transmitters, we might be able to distinguish different methods of transmission that would be the first clue to a divided planet.

If we received a robust SETI transmission and were able to decipher it, and especially if we were to receive multiple messages from a single planet, with messages arriving in different signal configurations, and in deciphering them we could reconstruct the political division of the planet into distinct factions, there is no reason we couldn’t start making quite subtle distinctions among the transmitters of signals. However, all this would be downstream from an initial reception. We can’t get to the point of distinguishing signals from a single source until we have multiple receptions of SETI signals from the source.

From my reading of SETI papers, the impression I get is the intuitive idea of civilization on other worlds being much like our own in the sense of having its origins in multiple distinct geographical locations, but eventually growing together as the agents responsible for civilization build out their respective civilizations until they meet each other. Presumably, this process of civilizational concrescence continues until the originally separate civilizations are lost in the one planetary civilization. This is, I think, not only a conception of civilization present in SETI, but that it is implicitly held by many today with no interest in SETI but looking at our own civilization on Earth and seeing it in the process of concrescence, but not yet fully grown together.

There is another facet of this intuitive grasp of the indifferent conception, and that is the idea that, since the earliest origins of civilization on Earth, there has always been some civilization existing somewhere on Earth, although over historical time these civilizations overlap in sequence; some are ending, some are beginning, some are reaching their zenith; some are declining. This is like Wittgenstein’s metaphor of a rope in which no single strand of fiber runs the entire length of the rope, but the rope nevertheless is a continuous length from one end to the other. Just so civilization on Earth: originating in several locations, enduring for a time, being replaced by other civilizations, and ultimately growing together into a single civilization. This, I think, is the intuitive content of the SETI conception of civilization, and these are reasonable assumptions to maintain. It wouldn’t take all that much work to develop this into a more substantive account of the object of SETI searches, but I am aware of no effort to do so.

Another wrinkle in this indifferent conception: the above sketch of planetary civilization supervenes on a planetary biosphere, and one of the factors that ties together all the civilizations on a given planet is their common biology. Further, if a civilization from a given planet spreads outward into the cosmos, it will take its biological heritage along with it. If and when human beings establish settlements away from Earth, we will have to reconstruct a considerable part of our terrestrial environment in order to provide ourselves with oxygen, food, and water, and to recycle our biological wastes.

Of course, one of the favorite ideas of SETI and the expansion hypothesis is the idea of a post-biological civilization that transcends its biological origins and expands into the cosmos in a non-biological form, precisely because of the difficulty of keeping biological bodies alive and comfortable in the harsh conditions of space. Even here, however, we haven’t fully taken leave of biology. If our assumption is that biological agents build the technology that transcends them, then something of the biological origins of the builders of the technology will be passed along into the technology. It could be argued that scientific and technological development within the context of a given biological agent and its mesophilic norms would determine that technology at least to some extent. A biological agent evolving on a world much hotter or much colder than ours would probably develop different technologies based on different materials and engineering techniques, and the distinctive ways in which a biological agent interacts with its worlds would be the assumption built into the technologies interacting with the cosmos at large.

These considerations suggest what I will call the Biological Derivation Hypothesis (BDH):

BDH — At least some of the biological parameters of the biological engineers of a given post-biological technology can be derived from that post-biological technology.

This is the weak form of the BDH, while the strong form is this:

SBDH — All of the biological parameters of the biological engineering of a given post-biological technology can be derived from that post-biological technology.

The distinction between weak and strong forms of the BDH will be a function of the kind and quantity of post-biological technology we have available to us. Like the above scenario of being able to reconstruct the political divisions of a planet by having sufficiently robust SETI evidence that allows for such a reconstruction, a single piece of post-biological technology will probably provide only limited knowledge of the species that built it. If, however, we are able to collect enough instances of post-biological technology, we may be able to make an exhaustive reconstruction of the engineering species. Especially if we were able to recover pre-post-biological technology — say, a spacesuit for the engineering species — we would stand a good chance of reconstructing much of the physiology of the engineering species. An artifact like a spacesuit comes under the consideration of kinds of evidence, this being a paradigmatic kind of evidence that would allow much more reconstruction that, say, discovering a solar panel built by another intelligent species.

The above distinction between the indifferent and the proper conception of planetary civilization has implications for other forms of emergent complexity. In particular, it has implications for biology, which is another planetary-scale emergent complexity. We can distinguish between two conceptions of planetary life, which we may call the indifferent and the proper conception. The indifferent conception of planetary scale life is that (analogous to civilization) life may have originated in a multiple geologically distinct locations, but eventually life spread over the entire planet and grew together into a single planetary-scale biosphere. Again, as with civilization, this planetary-scale life has been continuous for almost four billion years, but no single form of life is present for the entire history of the biosphere. Rather, life overlaps, with new species coming into existence even as other species are going extinct. Like the fibers in Wittgenstein’s rope metaphor, the unity and continuity of the biosphere is a function of many different forms of life that overlap and intersect over time.

The proper conception of planetary-scale life may be identified with James Lovelock’s Gaia Hypothesis, in which the biosphere itself is a living organism — a superorganism, to be sure, like a termite mound or a bee hive, but still an organism that self-regulates and so can maintain homeostasis on a changing Earth — planetary scale homeostasis. We know that Earth in its four billion years as a habitable and indeed as an inhabited planet has passed through periods of extreme cold and extreme heat, but these climatological extremes have never exceeded the ability of life to adapt to prevailing conditions. The homeostatic function of life on a planetary scale can be used to explain how life was able to form despite the sun being cooler in the past (the “Faint Young Sun” problem), and that life formed under these conditions was able not only able to adapt and survive, but it kept the surface of Earth within relatively clement parameters so that, for example, there has been liquid water on Earth’s surface for four billion years. This also suggests an explanation for conditions on Mars. The faint young sun problem is even more severe for Mars than it is for Earth, but we now have ample geological evidence that Mars had shallow seas early in its history. Whether life formed and existed briefly on Mars, or life never formed at all on Mars, life was never present at a threshold sufficient to maintain the Martian climate in homeostasis, so the planet freeze dried itself and its oceans evaporated.

The indifferent and proper conceptions of planetary-scale life are not mutually exclusive; the two could well coincide. So too for civilization: the indifferent and proper conceptions of planetary civilization are not mutually exclusive, and we could define a condition of civilization in which the two conceptions coincide.

A final reflection on the foregoing: in contemplating the history of life on Earth it is important to keep firmly in mind that the vast bulk of this history was microbial. “Animals” in any recognizable sense did not come into being until about 700 million years before present, and animals on land don’t arrive until hundreds of millions of years later. It is entirely possible that the formation of a planetary-scale biosphere lasted as long as the entire epoch of animals to date. The hundred million years or more of mammalian evolution is a mere rounding error at these time scales. If the terrestrial biosphere is properly planetary scale life, i.e., if Lovelock’s Gaia hypothesis holds, it holds for biospheres of microbes.