Through most of human history, people have tried to understand their world through reductive reasoning.
That is to say, they have been inclined to take things apart to see how they work. As Albert Láslo Barabáse write in his influential book Linked, “Reductionism was the driving force behind much of the 20th century’s scientific research. To compreend nature, it tells us, we must dechiper its components. The assumption is that once we understand the parts, it will be easy to grasp the whole. Divide and Conquer; the devil is in the details.
Therefore, for decades we have been forced to see the world through its constituents. We have been trained to study atoms and superstrings to understand the universe; molecules to comprehend life; individual genes to understand complex behavior; prophets to see the origins of fads and religions.” This way of thinking induces people to think they can understand a problem by dissecting it into its various parts. They can understand a person’s personality if they just tease out and investigate his genetic or environmental traits. This deductive mode is specially of conscious cognition–the sort of cognition that is linear and logical.
The problem with this approach is that it has trouble explaining dynamic complexity, the essential feature of a human being, a culture, or a society. So recently there has been a greater appreciation for the structure of emergent systems.
Emergent systems exists when different elements come together and produce something that is greater than the sum of their parts.
Or, to put it differently, the pieces of a system interact, and out of their interaction something entirely new emerges. For example, benign things like air and water come together and sometimes, through a certain pattern of interaction, a hurricane emerges. Sounds and syllables come together and produce a story that has its emotional power that is irreducible to its constituent parts.
Emergent systems don’t rely upon a central controller. Instead, once a pattern of interaction is established, it has a downward influence on the behavior of the components.
For example, let’s say an ant in a colony stumbles upon a new source of food. No dictator ant has to tell the colony to reorganize itself to harvest that source. Instead, one ant, in the course of his normal foraging, stumbles upon the food. Then a neighboring ant will notice and that ant’s change in direction, and than a neighbor of that ant will notice the change, and pretty soon, as Steven Johnson puts it, “Local information can lead to global wisdom.” The entire colony will have a pheromone superhighway to harvest the new food source.
A change has been quickly communicated through a system, and the whole colony mind has restructured itself to take advantage of this new circumstance. There has been no concsious decision to make the change. But a new set of arrangements has emerged, and once the custom has been set, future ants will automaticaly conform.
Emergent systems are really good at passing down customs accross hundreds or thousands of generations. As Deborah Gordon of Stanford discovered, if you put ants in a large plastic tray, they will build a colony. They will also build a cemetery for dead ants, and the cemetery will be as far as possible from the colony. No individual ant worked out of the geometry. In fact, each individual ant may be blind to the entire structure. Instead individual ants followed local cues.
There are emergent systems all around. The brain is an emergent system. And individual neuron in the brain does not contain an idea, say, of an apple. But of the pattern of firing of millions of neurons, the idea of an apple emerges.
The Social Animal, chapter 7, Norms