Lewin's style is excellent and I found him easy to read. Dr. Lewis found most insightful the discussion early on, on the concept of "emergence". We talk of vision as an emergent. Lewin talks of emergent global structures as being order which arising out of a complex dynamical system. The emphasize that often by studying only the components one would be hard pressed to see that what would emerge is that which does indeed emerge. If you knew all about the functions of the subsets of all the components that go into vision would vision be what you would predict would emerge if you didn't already know that this thing we call vision existed?

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