Sharp Blue: Thoughts on the classification of civilisations

Recently, I’ve been thinking about the classification of civilisations. There are really two types of classification scheme. The first type is descriptive and the second type predictive. Almost all current schemes fall into the “descriptive” category. These are systems that are really sets of labels for the successive stages in development of a single civilisation (or group of related civilisations). One well known example is the division of human prehistory and history in Europe and the Middle East into the Palaeolithic, Mesolithic, Neolithic, Bronze Age and Iron Age (of which the last two are “Civilisation” proper). Each of these divisions is characterised by a certain assemblage of technological artifacts. For example, the Mesolithic involves fishing nets and lines, the Neolithic agriculture and pottery, and the two “Civilised” phases some combination of cities, monumental architecture, writing and metal-working. But even within the limited scope of Europe and the Middle East, the scheme is problematic. Anatolia, for example, had an “aceramic Neolithic”.

Attempts to transfer descriptive schemes “sideways” to other regions of the the world have essentially failed. It seems that in the past, almost all civilisations have developed along their own lines, as determined by their cultural biases, local environmental potentialities and perhaps more than a little chance. Archaeologists studying Meso-America, for example, have long since discarded the Mesolithic/Neolithic/Bronze/Iron progression in favour of their own scheme that divides history into the Lithic, Archaic, Formative, Classic and Post-Classic periods. As in Europe, these periods are based on developments in technology and social organisation, but they aren’t the same developments! One extreme example is the society of the Incas, which was generally comparable with those of Sumeria or Egypt in terms of division of labour, monumental architecture, area controlled, artistic sophistication and the development of knowledge, but which had no writing and so would only be borderline “civilised” by a strictly applied Old World classification scheme. Likewise, the Mayan civilisation, which was perhaps the most advanced in America before Columbus, had no cities.

Now, if we’re talking about classifying civilisations on other planets or in the future of the solar system then we’re in the realm of predictive classification schemes, for the simple reason that no such civilisations are available to study. The broad-brush division of civilisations into Kardashev types might serve as the model for such schemes. If we had data on a civilisation that developed to the point at which it controlled all the energy of a world, then its star system, and then a galaxy, we would be able to use the Kardashev classification descriptively. If we saw lots of civilisations at various stages along this route (as we might have done, for example, if the searches for Dyson spheres [PDF] in the IRAS data had come back positive), we would be able to use it not just descriptively but, more importantly, predictively! This would be analogous to the piecing together of the main sequence of stellar evolution from snapshots of different stars. (Converting a spatial sample of civilisations and their relics into a temporal sequence of development will be at the heart of my “Hyperconnected Universe” novel if I ever find time to write it.)

However, the naive Kardashev model might be wrong, and so the Kardashev classification scheme might be useless. This could happen, for instance, if civilisations tend to only ever utilise a small fraction of a star’s power output: a society that controls 1% of the output of a hundred stars would be very different to one that controlled all the output of one star. For that matter, perhaps civilisations tend to use the Penrose process to extract rotational energy from black holes, or extract vacuum energy, or… Similarly, any other such classification scheme for advanced civilisations would embody a general model of the development, and will only be useful to the extent that the model is an accurate description of how civilisations develop.

So how likely to be true are general models of development? (Or, alternatively, how useful will classification schemes for civilisations be?) On the basis of the past, as discussed above, not very. Even if the development of each individual civilisation has been determined by its initial culture and environment in such a way that the consequences can be predicted from the initial conditions, these initial conditions have varied enough between civilisations that none can serve as a template for the others. Even societies that started out with the same social, cultural and technological “package” have diverged rapidly under different environmental influences, as might be seen most clearly in the diversification of the societies that spread outwards across the Pacific in the “Austronesian expansion”.

However, the future might be different: there might be increasingly strong attractors in societal development that kick in with technological advance. One possible example is artificial intelligence: superhumanly intelligent machines might all arrive at a set of universal principles (which are reached from all starting points) that then strongly channel social development. Another example might simply be the interconnections between technologies. If all you’ve invented is pottery, the wheel and writing then your society will likely be very different to one that has invented pottery, the wheel and the stirrup, whereas if you’ve invented many millions of things then they are each likely to be less important and at the same time more dependent on the others. (Perhaps the resolution of the mystery of the Great Silence is that there is such a strong attractor, and it’s a highly fatal one…) On the other hand, we can’t currently discern such attractors, so any classification scheme must be more nearly science fiction than futurology!