Privileged worlds, additivity and maximal risk

In ‘The unified theory of risk’ (2024) Jaakko Hirvelä and Niall Paterson consider the recent debate between the probabilistic, modal and normic theories of risk, and propose an intriguing new account – the titular unified theory . In this paper I focus on Hirvelä and Paterson’s criticisms of the normic theory, which are based on what they call the ‘privileged world problem’ and on the idea that risks ‘add up’. I will argue that these criticisms can, to an extent, be avoided by adopting a certain reinterpretation of the normic theory, particularly as it pertains to the notion of maximal risk . I then turn to the unified theory of risk and argue that, on close inspection, the theory is very similar to one of the rival theories that it purports to unify – namely, the probabilistic theory – and may share its shortcomings.