Sustainable development and social welfare

Sustainable development is a normative concept which involves trade-offs am ong social, ecological and economic objectives, and is required to sustain the integrity of the overall system. This is usefully formalized in terms o f a social welfare function which is based on an aggregate of individual pr eferences and, as a prerequisite of intergenerational equity and overall sy stem integrity, on a set of sustainability constraints. A 'sustainability-b ased social value function' is proposed to integrate these issues, and to g o beyond traditional conceptions of sustainability that are either based on a value principle of maintaining some aggregate of capital ('weak sustaina bility'), or stationary-state criteria of maintaining social, ecological an d economic assets constant over time ('strong sustainability'). Along with individual preferences and macroeconomic objectives, the proposed welfare f unction integrates principles of basic human needs ('critical economic capi tal'), integrity of the ecosystem ('critical ecological capital') and the s ocio-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.