Is there such a thing as irreducible complexity? Our current society is some orders of magnitude more complex than a hunter-gatherer society. What I mean is that the basic requirements of life: food, water, shelter; are provided by organized systems which require the labor of thousands of people and which no single person fully understands. These systems have evolved over millenia, though the complexity started increasing rapidly in the last two hundred years.
Although I said that no single person understands these systems, I think we all tend to believe that it would be possible if one tried. The systems are mostly designed to be decomposable, so that one part can change without affecting other parts, and they are mostly designed to fail safe, so that the failure of one component may cause degraded service but does not cause the system to stop working. Obviously in saying this I am using the language of programming, which is appropriate in that some computer programs are probably the most complex objects which humans have designed and built.
The significant difference, however, is that computer programs were in fact designed, and they were designed with an awareness of complexity. The systems which form our society were not designed; they evolved. Evolution can and does produce systems which are more complex than ones that humans would design. My question for today is whether evolution produces systems which are more complex than people can understand.
Our tools for understanding complexity amount to 1) building an abstract mathematical model of the system and learning how to manipulate that model; 2) breaking the system into smaller components, understanding the components individually and understanding how they fit together. Nobody has any idea how to apply a mathematical model to a biological system, but there has been considerable progress in breaking them up into components. It is still theoretically possible that some parts of a biological system are too complex to understand; perhaps the neurotransmitter system that presumably underlies consciousness can not be broken up into components in any reasonable way. However, while that is a theoretical possibility I’m not sure that many people truly believe it. Scientists do continue to make steady progress in understanding biological systems.
Biological systems are limited in their complexity by their size, by the constraints of their evolutionary history, and by the rigorous constraints of survival in an uncaring world. None of these limitations apply to systems created by humans. Human systems are limited in that any individual part must be comprehensible by a human, but the interconnection of those systems has no inherent limit in complexity.
So while it is clearly impossible for us to design a system which is too complex to understand, is it possible for one to evolve out of our society? Does the fact that economics is a failure as a predictive science suggest that that has already happened? Is it possible for us to develop more powerful tools of comprehension? If we did develop those tools, would we somehow use them to make systems still more complex?
What are the consequences of living in a system which is too complex to understand, if such a system is indeed possible? One of the lessons of state socialism was that planned economies don’t work. Was that only due to pervasive cynicism and opportunism among the bureaucrats, or was the problem really that no single person could grasp enough to plan the economy reasonably, or was the problem simply that they did not have the tools to do it? The market fundamentalists would say that a free market never fails, but anybody reading the newspaper today can see that that is not true, at least not in the short run which is what really matters for humans with a limited lifespan. I think that shows that while free market theory is a way to understand the complexity of our society, it simplifies too much, and fails to represent some significant aspects.
How do we benefit from the complexity of our society? Would it be better to make it simpler, or would we lose too much by doing so? Is it even possible to make it simpler without resorting to draconian coercion? Is there any natural limit to the complexity of society, other than the number of people involved?