The epistemological challenge of self-modifying systems: Governance and sustainability in the post-normal science era

In this paper, we conceptualize the difference among risk, uncertainty and ignorance and focus on a theoretical analysis of "modeling relation" applied to self-modifying systems within the framework of post-normal science. We provide an overview of the concept of risk and uncertainty elaborating on the work of F. Knight. We extend R. Rosen's theory of "modeling relation" originally aimed in natural science to the issue of science for governance. Knight's analysis of risk and uncertainty can be used to generate a list of various types of uncertainty involved in every stage to model self-modifying systems. Such a list is relevant for gaining insight into the issue of science for governance. It is important for those attempting to model sustainability, especially in the field of ecological economics, to be aware of the theoretical difference between models and similes for self-modifying systems. (c) 2005 Elsevier B.V. All rights reserved.