Sunday, October 14, 2007

Exploring Emergence

My last post described Dr. Saskida's view as sounding like "a species of emergentism," and I also noted that the mind/body view that I hold is of a similar species. Today, I was wandering drunkenly around the internet (with the assistance of Firefox plugin StumbleUpon) and came across this gem from the MIT Epistemology and Learning Center--it's an interactive essay on emergence!

First a few introductory words. When I was teaching philosophy of mind this summer at CTY (first session, not the class Eripsa and I taught), we played a game with the kids to help them understand emergence. We divided the class into two groups: scientists and particles. The particles were taken out to a large grassy field, and given instructions about how to behave. Half the particles were "negatively charged," and the other half were "positively charged;" normally, the two kinds of particles repelled each other--that is, when a + approached a -, the two flew apart at high speed. However, certain configurations of particles were stable (a ring consisting of two of each, for instance), and other arrangements would produce...unexpected behavior.

The kids playing the roles of scientists were not told any of this--they were just charged with figuring out all the rules governing the behavior of their classmates. To this end, they were allowed to pause the "simulation" (i.e. tell the particle kids to freeze), then reposition, remove, or add any classmates from the field. By judiciously using these techniques, the kids were able to figure out that, while the basic rules of the system were pretty simple, things got significantly more complicated when the "particles" were arranged in certain ways: this is the basic principle behind emergence.

This activity was awesome, but it requires a few resources that not everyone has access to (not the least of which is the energy level of a 14 year old). Enter the Exploring Emergence Active Essay from MIT. This really clever series of web pages uses Java applets to explore emergent properties--you are presented with a black field, on which you can click anywhere to produce a small white square. Once you're satisfied with the placement of squares, you can start the simulation, which causes the squares to interact and move in certain ways described by rather simple rules (e.g. if a neighboring square is on, turn it off, then turn on two randomly selected neighbors). Starting with less complicated builds, the active essay shows how quickly mind-boggling complexity can arise from seemingly simplistic systems.

What's the point of all this? Well, many people (myself included) think that the relationship between mental states (e.g. beliefs) and brain states (e.g. neuronal activity) is an emergent one--that is, that while (relatively) simple physical laws govern the low-level action of the brain, the particular arrangement of molecules in that organ generate higher level complexities that seem quite apart from the rather deterministically simple behavior of the individual "particles" making up the brain. This kind of view has the advantage of avoiding ontological dualism (that is, it has the advantage of not postulating any non-physical substance as making up the mind), as well as the advantage of not requiring us to jettison the seemingly inescapable fact that we really do have minds.

I urge everyone to run through that active essay. It doesn't take too long to finish (maybe 15 or 20 minutes if you take it slowly), and is really fun and interesting to explore.


Neil said...

Great blog. Please visit my blog, awarenessforallpeople, and tell me what you think. I'm trying to put together something, maybe a book, that explains what the mind is. I could possibly use your help. Good luck on working toward your Ph.D.
Neil Crenshaw

Jon said...

Thanks for the compliment, Neil! I'll certainly check your blog out and post a comment or two.