The concept of the power of judgement goes back to the Greek word phronesis which means prudence. Aristotle dealt with it, and in the 19th century Kant wrote his ground-breaking Critique of the Power of Judgement.
Mainstream Economics traditionally is good at modelling predictable situations as well as situations with calculable risk. However, environmental issues generally evolve over the long-term, which entails surprise and ignorance. To this end we need concepts hitherto not employed by Mainstream Economics; in particular we need to consider the concept of the power of judgement. Although this is a philosophical concept, we all are aware of it in everyday life. It is the ability to react intuitively in a new situation. A judge or a doctor who is confronted with a new case needs the capability of power of judgement to pass an adequate judgement or find an appropriate treatment. Ecological Economics makes use of the power of judgement.
This concept enables us to discuss, in a non-scientific but nevertheless rational manner, long-term problems, evolutionary in nature, and our confrontation with uncertainty and ignorance.
An example of the power of judgement is the application of the precautionary principle which protects us from the consequences of actions that otherwise would take us completely by surprise. The example of Fukushima shows how that catastrophe could have been avoided had the power of judgement been applied.