Progress is not the same thing as complexity increase. While I agree that there can be upper bounds on complexity increase in evolution, this doesn't really have that much relevance to the question of whether evolution has any cumulative direction. The latter is something I consider to be an open question.
As any engineer knows, great increases in capability often occur through the removal of complexity, not its addition. This happens more frequently than you'd think. It's part of why, for instance, computers have gotten better, faster, and cheaper. If you ...
Allow me to clarify douglas a bit if I can. Correct me if I'm wrong.
What douglas is (I think) invoking here is a phenomenon called the evolution of evolvability. Essentially the idea is that evolution is not quite as blind or random as pure classical Darwinism would have it, but that it evolves. Evolution evolves, recursively. Lineages that do a better job exploring fitness landscape space do a better job surviving, and so therefore their genes tend to do a better job surviving as well. Evolution therefore favors the emergence of genetic systems that aid e... (read more)