Sir

As they try to dispel the “myth of market prices”, Don Fullerton and Robert Stavins argue that economists are not exclusively concerned with the financial value of things (“How economists see the environment”, Nature 395, 433–434; 1998).

They say, for example, that the value of damages to health from environmental pollution not only includes healthcare costs and wage losses, but also “pain and suffering”. The goal of economic analysis being to measure the total value of the loss that individuals incur, “economists insist on trying to convert all these disparate values into monetary terms because a common unit of measure is needed to be able to add them up”.

But, unfortunately, neither a disappeared species nor a deceased beloved one can be bought back to life. What is the point of pricing things that no one can buy or sell? Doing so is erroneous and dangerous. It is easily understandable how the need for rational policies leads to the kind of analysis described by Fullerton and Stavins. However, the world does not fit entirely in the concepts of economic science, and sometimes rational decisions are simply not possible. In those cases, clearly stated moral principles, not shaky science, should guide decision-makers.