I was sitting on my dock, looking at the water, trying to figure out why schools of thought are so insular. Schools of minnows provided the answer.
It is no secret that academic fields have rigid boundaries. Quiet insularity would be bad enough, but many are belligerent towards other groups, especially others that claim the same territory. Philosophy, literary criticism, and history each have many competing schools of thought. Social, cultural, biological, clinical, behavioral, cognitive, personality, and developmental psychology are remarkably separate fields. Cultural and biological anthropologists hardly talk. Science and postmodernism repel each other as if each had arrays of magnets with north poles facing outwards . Everyone knows the world would be better if boundaries were more blurry, but interdisciplinary programs come and go, and schools of thought maintain their insularity. Why?
I watched a school of minnows swirling in the shallows, flashing silver in gorgeous unison, splitting, then merging, then splitting and merging again. No choreographer could enforce such gorgeous coordination, but it emerges spontaneously from each minnow swimming steadily towards the constantly moving center of the school. How did selection shaped minnow brain wired to motivate swimming towards the center? As I watched, one minnow turned right when the group turned left; it was alone for one second, then it was grabbed by a bluegill.
Humans who stray from the centers of schools of thought don't get snached by predators, but they are often attacked by other humans who are safely within groups, making the territory outside a no-man's-land. Has this been happening long enough to shape a general tendency to move mentally towards the ideological center of a group? Or do we all just learn, from experience, that deviation is dangerous, but nonetheless tempting, and sometimes worth it, because the most fertile ground is between the silos.