The semantic body

Russell Turpin
Sun, 26 Aug 2001 17:21:29 -0500

(Random thoughts, after an exhausting weekend.)

I know it is unfair to pick too much at an example
that perhaps it intended more as analogy than 
illustrative case in point. And I mean no offense
to Clay Shirky by this. But the more I think about
the biological example, the more convinced I am
(1) that it is nothing like the internet, and (2) that
one of the points pressed from the analogy is 

It is true that the complexity of the cell is greater
than the complexity of its membrane interface, and
so on with tissues, and organs. But a tremendous
difference between biological systems and the
internet is that the former are hardwired. Nerve
cells do not communicate with arbitrary other
nerve cells, but with specific other nerve cells,
muscles, and sensory organs. The blood stream
provides a broadcast messaging system, of
course, but it it filtered quite a bit in the different
organs. To then point out that there are relatively
few biochemical intermediaries overlooks the fact 
that each of these may have different meaning
-- different "semantics" -- in each of the places
where it is meaningful. Nitric oxide in the 
amygdala may carry some emotional meaning,
in the hippocampus, it may affect memory, in
some other part of the brain, yet something 
else, and in the corpus spongiosum, it causes a 
boner. One can no more say the semantics
is simple because of the small number of 
biochemical intermediaries than one can say
the semantics of the world's digital protocols
and file formats are simple, because they all 
use a relatively small number of byte values,
0 to 255. (And in the first case, "relatively 
small" is at least a few thousand.)

Bottom line: The body works through a
hard-wired architecture involving tens of 
thousands of specialized protocols. These 
carry deep and subtle semantics that are still
causing biochemists and physiologists to 
scratch their head, despite the *relatively* 
small number of biochemical "symbols" that
are used and reused in all of these. I'm not 
sure what one should conclude from this 
about the internet.