ABSTRACT
The appeal of cost-benefit analysis, like that of its parent, utilitarianism, is that it promises a decision procedure that gives a rational resolution of apparently conflicting preferences and appraisals. It does so by the use of algorithmic procedures which give determinate answers to any problem. There is, in the economic literature, a widespread assumption that nothing else could provide a rational solution. In this chapter I argue that the existence of plural and incommensurable values in environmental appraisal reveals that the promise of cost-benefit analysis is illusory. Moreover its problems raise deeper difficulties for its foundations in neo-classical economics. The appeal of cost-benefit analysis depends on a cramped and mistaken account of rationality-one that misidentifies rational choices with those that can be arrived at by way of algorithmic procedures. In the final two sections I examine the implications for political economy of this mistaken account of practical rationality.
