This chapter discusses philosophical reflections on the intellectual adventure of conducting Integrated Assessment (IA) Focus Groups with citizens, as presented in this volume. The task of this exercise was ambitious: to bridge the gap between sustainability science and democratic debate in the climate domain. The science component was mainly represented by models, most (although not all) having the appearance of describing future states of the global climate and their consequences for human society. At first it could seem a daunting, indeed, overwhelming task: it was hard to see how lay participants could meaningfully relate to models whose construction required very special expertise in mathematics and software engineering; and whose comprehension required knowledge of climate science. But having witnessed the debates among the modelers themselves, the research team already knew that IA models are quite problematic products of science. It is freely accepted, even emphasized, among the experts that the models do not provide simple predictions; and so their epistemic status and policy relevance were already open to question. In addition, there was the knowledge that experts are usually “laypersons” outside their specialties, and that policy-makers are generally no more knowledgeable than ordinary citizens. And, in any event, the democratic process involves debate over issues where both expert and lay voices are heard. Hence the IA models were an appropriate vehicle for developing a many-sided dialogue on basic issues.
In the event, the involvement of this “extended peer community” proved far less difficult than anticipated.