Requisite variety: more on Gaia

The purpose of this paper is to mention a set of suggestions for analysing the current financial crisis, but with reservations about the usefulness of one based on Ashby's principle of requisite variety. The reservations are supported by reference to a mechanism of chemotaxis in bacteria. A recent publication concerning the Gaia hypothesis and global warming is reviewed.

The aim is to review developments on the internet, especially those of general cybernetic interest.

The significance of complexity, in government and management, is not disputed, but doubts are expressed about validity of laws that are purported to treat it quantitatively. A pessimistic view of world future is due to James Lovelock, the originator of the Gaia hypothesis, though there is some reason to believe he is more hopeful than is suggested in an interview.

The reservations about Ashby's treatment of complexity are essentially theoretical and do not negate findings based on its robust and imprecise application. Lovelock indicates a means of saving the Earth from disastrous climate change but has little hope that it will be implemented.

It is hoped this is a valuable periodic review.