Sustainable development and social welfare

Sustainable development is a normative concept which involves trade-offs among social, ecological and economic objectives, and is required to sustain the integrity of the overall system. This is usefully formalized in terms of a social welfare function which is based on an aggregate of individual preferences and, as a prerequisite of intergenerational equity and overall system integrity, on a set of sustainability constraints. A 'sustainability-based social value function' is proposed to integrate these issues, and to go beyond traditional conceptions of sustainability that are either based on a value principle of maintaining some aggregate of capital ('weak sustainability'), or stationary-state criteria of maintaining social, ecological and economic assets constant over time ('strong sustainability'). Along with individual preferences and macroeconomic objectives, the proposed welfare function integrates principles of basic human needs ('critical economic capital'), integrity of the ecosystem ('critical ecological capital') and the socio-cultural system ('critical social capital'). This implies restrictions of the social opportunity space within which sustainable develop ment can proceed and the new value function is defined. (C) 2000 Elsevier Science B.V. All rights reserved.