Your nervous system is as complex a physical object as there is in the universe, so far as we know: 12 billion cells, each of them a complex structure with up to sixty thousand synaptic points of connection with other cells. It is also the one piece of physical real estate of which you have an inside view, so to speak, since the events of your inner life, and the experiences through which you learn about the external world, are all immediate manifestations of what is going on in there. Since you can also study your central nervous system by external observation and experiment as you study other physical systems - by exposing its outer edges, such as the retina, to bombardment by suitably produced and therefore informative physical impulses - there arises a problem about how to bring these two views of yourself together.

LRB 1 October 1987 | PDF Download