Speaking of emergent properties ---
There is a new book out by Steven Johnson called "Emergence",
Scribner, N.Y. specifically about the idea of emergent properties. It
is reviewed in todays (Sunday, Sept. 9, 2001) N.Y. Times book review
The subtitle is "The connected lives of ants, brains, cities, and
software." It seems to be a non-technical science-journalism type of
work, but should have a lot of information of interest to those
following this thread.