[From Bill Powers (920816.1000)]
Fred Keijser (920813) --
Hello, Fred, and welcome to our conversation.
I have had some contact with Maturana; in some ways we have similar views,
but we diverge greatly in other ways. Maturana's concept of autopoiesis is
not worked out in any detail -- it's just a statement that some systems are
"self-making." What such a system would have to be able to do in order to
make itself isn't explained.
There's a discussion of my views on Maturana in Living Control Systems II,
available from Greg Williams.
My biggest argument with Maturana regards his "closed" nervous system. If
you're going to assume a model of a nervous system, this entails the whole
theoretical structure that is behind it: neurology, physics, chemistry, and
so on. So to claim that the nervous system is structurally closed is only a
half-baked epistemology. If you admit of a physical nervous system, then to
finish baking the idea you have to include the relationships of the nervous
system to the physical external world -- which Maturana refers to as the
"medium" and treats as an unknown black box. In my opinion he doesn't have
a workable model -- only a sort of metaphor.
As to "representation," PCT addresses it in two ways. There is perception,
which is a signal-based representation of aspects of the current external
world. There are also reference signals, which are signal-based
representations of the intended state of the perceptions. The perceptual
signals arise from sensory interaction with the external world. The
reference signals are internally generated. Which aspect of representation
are you concerned with?