Slippery slope arguments as precautionary arguments: a new way of understanding the concern about geoengineering research

It has been argued that geoengineering research should not be pursued because of a slippery slope from research to problematic deployment. These arguments have been thought weak or defective on the basis of interpretations that treat the arguments as relying on dubious premises. The paper urges a new interpretation of these arguments as precautionary arguments, i.e. as relying on a precautionary principle. This interpretation helps us better appreciate the potential normative force of the worries, their potential policy relevance, and the kind of evidence required by slippery slope arguments. Understood as precautionary arguments, it is clear that slippery slope arguments against geoengineering capture concerns that are worth taking seriously.