Unifying 'the' Precautionary Principle? Justification and Reflective Equilibrium

The precautionary principle (PP) is an influential principle for making decisions when facing uncertain, but potentially severe, harm. However, there is a persistent disagreement about what the principle entails, exactly. It exists in a multitude of formulations and has potentially conflicting ideas associated with it. Is there even such a thing as 'the precautionary principle'? This paper analyses the debate between unificationists and pluralists about 'the PP', arguing that the debate is hindered by neglecting the question of justification. It introduces reflective equilibrium as a method of justification, and sketches how it could be applied to justify a PP.