I have critically reviewed two distinct bodies of work in computational autopoiesis above--the original model of Varela et. al., and the developments of that by Zeleny. These are certain similarities in my comments. In both cases I have identified anomalies or difficulties of interpretation of the published results. However, the final conclusions are quite different. In the case of the original model, it proved possible to locate the source code (or, at least, a close relative) on which the results were based; as a result, the substantive difficulties were fully resolved. For Zeleny's work, unfortunately, the source code is apparently lost; definitive resolution of questions relating to it, at this stage, is therefore extremely difficult, if not impossible.
I should emphasize that these differing outcomes are largely due to chance--the fortuitous re-discovery of the Varela documents--rather than design. However, regardless of that, they suggest a methodological lesson worth digesting. At the time of the original publications considered above, the technological facilities were not generally available to support easy distribution or access to accompanying code--but this is no longer the case. I would suggest therefore that as a general principle, published reports on computer models of ALife should be accompanied by access to the program code for the models on the World Wide Web; and indeed, that practice has now been followed in the cases of the surviving documents from Varela et. al.  and the successful modern re-implementation [28,33].
Copyright © 2004 All Rights Reserved.