Use of Modelling
One of the classic uses of simulation is for prediction. However, this is not the option we have chosen. The long-term economic and social future can not be predicted, although it can be partially decidable according to the hypothesis underlying the "patrimonial approach" (De Montgolfier and Natali, 1988; Ollagnon, 1989). "Because the very long term is beyond the scope of prediction, if we wish to take it into account in the analysis of environmental problems, we must give ourselves very long-term reference points or objectives to guide the possible or impossible pathways of development. The long-term approach must inevitably be based on a scenario" (Weber, 1993).The rules are legitimate in the stakeholders' eyes because they are the result of interaction between stakeholders and they incorporate particular perceptions.
Stakeholders can "decide" very long-term objectives on the basis of a shared conception of how the present situation should evolve. The scenarios which enable these objectives to be reached can then be discussed on that basis. The entire mediation approach presupposes that the stakeholders are well informed of the issues dividing them and of the fact that they all have an interest in solving the original problem.
The challenge of the initialization phase is to allow stakeholders to express how they perceive the present situation and its evolution. When a "map of perceptions"-all equally legitimate and equally subjective-has been established and discussed, the stakeholders are asked to discuss whether it is acceptable to continue with existing tendencies. How can simulations be involved in this process, i.e. how can they help stakeholders to manage resources? We are trying to develop the concept of companion modelling using multi-agent systems. The ideas presented below are part of an approach which is now being implemented although it has only been partially tested. The approach is undoubtedly original in terms of its use of multi-agent systems, however, it has already been used by several researchers (Ostrom, 1990; Burton, 1994) whose work has provided the basis for our studies. Mermet (1992) and Piveteau (1994) have done a great deal of work-using role playing-on the relation between the patrimonial approach and the placing of stakeholders in an experimental situation. Our rationale is similar to that of these authors and we propose that the MAS modelling approach be put in this context.
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Mermet, L. 1992. Stratégies pour la gestion de l'environnement. L'Harmattan. 255 p.
de Montgolfier, and Natali, J.M. 1988. Le patrimoine du futur, Economica. 248 p.
Ollagnon, H., 1989. Une approche patrimoniale de la qualité du milieu naturel. Pages 258-268 in: Mathieu N. and Jollivet M. (eds). "Du rural à l'environnement, la question de la Nature aujourd'hui". L'Harmattan, Paris.
Ostrom, E. 1990. Governing the commons. The evolution of Institutions for collective action. Cambridge University Press, 280 p.
Piveteau, V. 1994. L'avenir a long terme des zones rurales fragiles, approche par le jeu prospectif d'une quetsion complexe. PhD thesis, Paris 1 University.
Weber, J., and Bailly, D. 1993. Prévoir c'est gouverner. Nat. Sci. Soc. 1(1): 59-64.