Emergence

Emergence is a fascinating philosophical notion that has been applied to an incredibly diverse array of concepts, from artificial intelligence to hurricanes to theory of mind. In fact, I learned about emergence from reading a philosophy paper describing baseball. Emergence refers to the way new phenomena can arise from simple interactions between many players. There are many individual people on a baseball team: the shortstop, the pitcher, the right outfielder. None of those people, individually, demonstrates "teamwork." You don't say, "Wow, that catcher has teamwork." But you take all these individual people and have them interact, and sometimes, you can get the property of "teamwork" to emerge. A strong view of emergence means that systems have properties that are irreducible to the system's constituents. Something new comes out; the whole is more than the sum of its parts.

"Although strong emergence is logically possible, it is uncomfortably like magic. How does an irreducible but supervenient downward causal power arise, since by definition it cannot be due to the aggregation of the micro-level potentialities? Such causal powers would be quite unlike anything within our scientific ken" (Mark Bedau).

I believe strong emergence may explain a lot of scientific phenomena. A single neuron can't "think." It's just made up of cell membrane and mitochondria and sodium channels. It fires all-or-nothing action potentials. It's pretty dumb. But you take a few of them and have them interact. They can start to do cool things, modulating each other's signals, affecting each other's growth. Wikipedia says there are anywhere from 100 billion to 100 trillion synapses. Maybe - just maybe - that's enough to create these unbelievably remarkable properties "thinking" and "consciousness." These higher level functions somehow result from the interactions of all the neurons, though no individual cell has such properties.

I've spent a considerable amount of time thinking about this topic. It has become the mainstay for explaining a ridiculous number of things, from how ant colonies work to architecture to friction. It seems like a simple idea, yet it has fundamental implications about science. If certain properties of a system emerge from complex interactions of its constituents, then "reductionist" science of breaking down problems into its parts will give little insight into the emergent properties. Indeed, in the last decade or so, there has been a great interest in "systems biology" because of this.

References: Wikipedia.