Making decisions based on risks is not easy, but commonplace. The problem with COVID-19 is that so many risks are unknown, as probability distributions are wanting. Moreover, decisions based on fundamental uncertainty tend to be speculative and potentially harmful.⁶ Decisions based on ambiguity “are not just potentially misleading — they are a fundamental contradiction in terms.”⁸ Therefore it is crucial to clarify definitions. Additionally, ignorance poses great challenges, as we do not know what we do not know – and hence where to search for solutions.