Emergence: Mystical Science? February 26, 2009Posted by C. Steves in Nuts and Bolts.
To ancient humans, the sight and sound of lightning and thunder must have been a baffling site to see. For thousands of years, I’m sure that humans would cower and shake like dogs while waiting out a thunderstorm. But the ancient Greeks were not satisfied with not understanding this meteorological phenomenon, and decided to attribute it to the expression of anger and discontentment of the god Zeus. They created a theory that attempted to explain a system they did not understand, an un-testable, un-falsifiable theory that could only hope to provide an explanation for these mind-boggling occurrences. This may very well be an early example of emergent theory.
Of course, today we understand the environmental causes of lighting and thunder, and in the Zeus explanation of the ancient Greeks, there is no attempt to use any sort of scientific reasoning to explain them. We will see later that this might be an appeal to a theory of “strong emergence”. This gets us to our central issue; do emergent theories present us with any logical explanations of observable phenomenon? Do they have any clout, or are they merely wisps of past thoughts and theories rising into the atmosphere with nothing to hold them together?
Emergent theories are theories that attempt to explain the creation of complex systems and properties from a selection of simpler, less intricate properties. For the most part, these theories can be broken up into two classes, “strong” and “weak” emergence.
The scientific community essentially accepts weak emergence, although it’s more of a tacit acceptance rather than an explicit claim in most cases. Weak emergence can be seen all around us in our everyday lives. Some common examples include:
1) Cities: Cities are giant organisms with complex patterns and behaviors that are all taking place with very precise input from the people living in it, and they sometimes arise with little or no planning or foresight.
2) Ant Colonies: Contrary to popular belief, the queen only creates more ants for the colony but has no directorial role, the colony is self regulating and functions as one large organism with no centralized “leader”.
Weak emergence can be generalized as systems that have patterns emerging from simple properties, but the patterns can be traced back through the constituent elements creating them.
Strong emergence on the other hand, consists of patterns that cannot be traced back through the constituent properties. In other words, somewhere along the line of evolution of the patterns, something is “injected” from somewhere within our outside the system that cannot be predicted, identified, or explained. There is a supervenience of a complex pattern that is greater than the sum of its parts. Some examples of strong emergence include:
1) The Mind-Brain Problem: Psychologists and biologists have yet to uncover what exactly happens in the brain to create consciousness and awareness. As far as we know, there is (as of yet) no explainable, traceable path from the constituent neurons and parts of the brain to the higher-level operation of the mind.
2) Cosmology: Although we are currently researching the origins of the universe and the cosmos, we still have little or no information to explain what happened before the big bang, what caused it, and how the material or energy was created.
Now that we have an idea of what constitutes emergence (strong and weak) we can get back to considering the proper place of emergence and emergent theories in science. For the most part, scientific theories are considered to have explanatory power. They provide concepts and generalizations about how the world around us works (the finer points of what a theory does and consists of are, of course, up for debate).
This, I believe, is where emergence is snagged. Consider weak emergence: an emergent theory will provide no additional information about a system of weak emergence that could not be gleaned by examining the interactions of the constituent parts and following their outcomes. There is no generalization provided about the system, and there is no information supplied that will help an observer make sense of any other weak emergent system. In fact, it might be analogous to the simple mathematical statement that 1+1=2.
Now consider strong emergence. Strong emergent systems essentially produce outcomes that are un-predictable, un-testable, and generally unknowable. It is in the very definition of a strong emergent system, that the properties created are greater than and irreducible to the sum of the parts. Essentially, this means that an emergent theory would be of no use in the physical sciences because it would do literally nothing for us other than state “This property is irreducible to it’s constituent parts”. What good is that information to science as a whole?
Emergent theories have been developing for many years, and there is nothing to say that with more research and time invested in them they won’t someday produce valid, worthwhile results that may be applicable to the physical sciences. However, until they can meet the criteria set forth and generally agreed upon by scientists all over the world and provide them with something other than a summation of knowledge they already have, they will be ostracized from the scientific community.