Trade-offs between conflicting goals
Clearly, there are conflicts between these goals. More equity may mean less efficiency. In the short term, it may not be possible to meet the needs of the present without consuming resources, for example by burning oil or clearing areas of natural forest. Decision-makers have to consider the trade-off between different goals but, if the system as a whole is to survive, the use of natural assets must be compensated by the development of human or physical assets of equal or greater worth.