The Emergent System

The concept of emergence seems to be cropping up everywhere one turns these days. The term is used to describe not only new events in organized religion, as described in the book I reviewed last week, but many other examples of otherwise unexplained behavior in the social sciences, such as dynamics in financial markets.

Emergent properties are collective properties, which means they are properties of collections, not properties of individual parts. The cause can often be traced back to the interactions between the parts of which a system is made.

Often the nature of those interactions is more important than the identity of the parts. Thus, flocking behaviors are observed in systems composed of insects, birds or even people, as seen in the accompanying photo. This concept has found a use in the computer science world where swarm intelligence, a type of artificial intelligence, is used to control flocks, or swarms, of robots.

The term "emergence" has been around for awhile and can be traced back to systems theory. Systems theory has also been around for awhile, going back to the 1950s, but it was not until 1972 when Philip Anderson wrote an article in Science entitled "More is Different," that scientists really began to grapple with the fact that systems are different than the isolated parts which collectively make up the system.

In this seminal article, Anderson wrote:

"The ability to reduce everything to simple fundamental laws does not imply the ability to start from those laws and reconstruct the universe...At each level of complexity entirely new properties appear. Psychology is not applied biology, nor is biology applied chemistry. We can now see that the whole becomes not merely more, but very different from the sum of its parts."

This idea that the whole is more from the sum of its parts is one of the main reasons that the emergence concept has been so compelling. When a new quality, or new behaviors, emerge from a simpler system we scientists long for a theory or explanation.

So far, our understanding of emergent behavior is only partial. We understand that the interactions between the parts of the system is a key feature of the mechanism that leads to emergence. We also understand that the behavior of the system as a whole can feed back on the parts which make it up, changing the behaviors of those parts.

It is this last aspect of emergence that makes it seem more than a little scary to those who first hear about it. If we are the parts and the system is society, the idea of the "system" imposing its will on us can be quite frightening. Just what is this "system" that is imposing its behavior on us? And is it something that I, as an individual, have any choice about?

This topic is a deep and intricate one and I will have much more to say about the science of emergence in future posts - stay tuned!