Reality is complex, and often does not lend itself to generalization or simplifying explanations. Yet at the same time, explaining reality often requires the shaping of notions and concepts of it through generalization and the reduction of complexity. This tension between complexity and particularity on the one hand and generalization and the search for abstracting explanatory patterns on the other is beautifully illustrated by two recently released publications on precaution and risk regulation in the United States and Europe, namely “The Politics of Precaution” by David Vogel1 and “The Reality of Precaution” edited by Jonathan Wiener, Michael Rogers, James Hammitt, and Peter Sand.

Both books together can be seen as the latest significant contribution to the ongoing debate on the role of the precautionary principle in risk regulation in a comparative EU-US perspective. Both contributions are significant in that they consolidate the trend towards an empirically informed analysis of the actual practice of the application of precaution in risk regulation.

Two recently published volumes on the concept of precaution as it is variously understood and applied across the United States and in Europe make for a fascinating comparative analysis. They also respectively offer some undoubted and invaluable insights into the subject. Sadly neither really addresses how precaution came of age or why.