The “Four Spheres” framework for sustainability

This paper presents in a synthetic way, a complex systems perspective on sustainability that highlights systems integrity and ethical integrity as complements. Sustainability is characterised as coevolution of economic, social and environmental systems respecting a dynamic “triple bottom line”-the simultaneous satisfaction of quality/performance goals pertaining to each of the three spheres. The theme of system regulation and governance leads to demarcation of a fourth fundamental category of organisation, the political sphere whose role is regulation of the economic and social spheres and thus of relations with (and within) the environmental sphere. Perspectives for the application of this “Tetrahedral Model” in sustainability science and policy analyses are outlined, relating to the “four capitals” and to the question of monetary evaluation of changes in social and environmental domains. The paper concludes by making a link between the triple bottom line, complexity and deliberation in sustainability politics.