Incommensurability and monetary valuation

At the very heart of environmental cost-benefit analysis (CBA) is the claim that benefits and costs can be expressed in terms of money and hence made comparable. In particular, CBA puts all benefits and costs on a cardinal, monetary scale: it assumes monetary commensurability. A significant literature in ethics and political philosophy has arisen which doubts this assumption, but has so far had little impact on the theory or practice of CBA. In light of this, the paper assesses the defense of monetary commensurability offered by cost-benefit analysts and the wider economics literature.