In defence of the precautionary principle

The precautionary principle is widely advocated, especially in Europe, but also much attacked. In this paper the principle will first be outlined and then some of the common criticisms discussed. One in particular will be examined in some depth; the criticism is that it is inherently paradoxical. The paradox supposedly arises because if the principle is applied to some action that is potentially harmful, it should also be applied to that application of it which is also potentially harmful, because it stops an action that is beneficial. Here it will be argued that the precautionary principle is not paradoxical and that it is important and useful.