Complexity and Natural Systems

The world is so complex that we don’t know how complex it is.

We have been tricked by our own success. In simple domains, we marvel at our own engineering and imagine it could be duplicated in complex domains. But bridges, rockets, and computers are extraordinarily simple compared to the biological, social, political, or economic world. Engineering in complex domains is frequently a bad idea—the wrong levers get yanked and end up causing more harm than good.

Fortunately, Nature can already handle the complexity of the world through its own existing systems. The fact that a system is naturally occurring demonstrates it has been able to successfully handle the complexity of the world.

Two examples come to mind: the economy and the immune system.

Economic Complexity

The fundamental problem of economics—the fact that scarcity exists in the world—results in unfathomable complexity. Billions of humans need stuff every minute of every day. If we tried to map out, plan for, and engineer every aspect of an economy for even a small neighborhood (or even a single good, for that matter), we would get immediately overwhelmed by its complexity. It’s beyond our engineering capacity.

And yet, Nature handles this complexity all by itself. People left to their own devices naturally end up coordinating to produce the goods they need to survive and thrive. There is no engineering required.

The Immune System

The human body is the most complex entity in the known universe, and we are not even close to understanding how complex it is. We do know enough to say that humans have weaknesses; some stuff in the environment kills us. But figuring out what stuff is dangerous—and by what mechanism it kills—is impossibly complex.

We have tried to engineer around this complexity with mixed success. The most famous example is vaccines, which are held up as a triumph of science and engineering. Yet upon closer inspection, it’s clear their benefits have been overstated and risks understated. The magnitude of these errors is still being researched.

More fundamentally, much of the real-world effects of vaccination are still unknown, simply due to the complexity involved. And because of the social stigma attached, few people are seriously investigating the topic. As a general principle, our default position should be skepticism towards yanking levers in complex systems.

Yet, Nature handles this complexity by itself, and it has for a long time. We have immune systems that have demonstrated the capacity to handle the unfathomable complexity and hostility of the natural world.

(Take chicken pox as an example to ponder. What’s likely to be better method for immunization: universal vaccination or pox parties? To use an insurance analogy, we can say that, at the very least, the pox party provides full complexity-coverage, while the vaccine provides an unknown amount.)

Naturalism and Complexity

It has become cliche to appeal to “natural methods” to solve problems. But it makes a great deal of sense in the context of complexity. If Nature has already come up with a working system to solve problems, it’s likely that it can handle more complexity than engineered systems. And it’s likely taking into account variables that we don’t even know exist.

Unfortunately, due to the stubbornness of the complexity problem, the naturalistic approach is not a universally superior method. There are exceptions—otherwise that would be too easy. We face a great intellectual challenge to figure out which natural systems need the intervention of engineers, and which need to be left alone.