Institute for Futures Studies. Working paper 2025:1 Abstract Extinction risk refers to the possibility of the extinction of the human species, and is the subject of a growing field of study. In this con   We present here an argument in favor of the time of perils hypothesis. We argue that, according to several prominent theories in the field of international relations (IR), humanity (absent an extinction event) is likely to be unified under a world system of governance. By a “world system of governance” (WSG), we mean a global set of institutions, norms and structures that can settle dis­putes, promote trust and cooperation, and reduce great power security compete­tion. We explore the most prominent theories in international relations, which include: realism, liberalism and constructivism, and how these theories propose the emergence of a global system of governance. We conclude that a WSG will, if it emerges, have a significant impact on reducing extinction risk, including risks from emerging technologies, biorisk and non-anthropogenic risks. This argument, linking IR theory to existential risk is, to our knowledge, novel and potentially significant in the context of ascertaining whether existential risk prevention has astronomical value in expectation due to the vast number of potential lives that could exist in the future.                                                  

Mind 130(520), 2021 Abstract The Bayesian maxim for rational learning could be described asconservative changefrom one probabilistic belief orcredencefunction to another in response to new information. ). But can this conservative-change maxim be extended to revising one’s credences in response to entertaining propositions or concepts of which one was previously unaware? The economists,) make a proposal in this spirit. Philosophers have adopted effectively the same rule: revision in response to growing awareness should not affect the relative probabilities of propositions in one’s ‘old’ epistemic state. The rule is compelling, but only under the assumptions that its advocates introduce. It is not a general requirement of rationality, or so we argue. We provide informal counterexamples. And we show that, when awareness grows, the boundary between one’s ‘old’ and ‘new’ epistemic commitments is blurred. Accordingly, there is no general notion of conservative change in this setting.

An individual human can maintain stable social relationships with about 150 people. This is the proposition known as ‘Dunbar’s number’ – that the architecture of the human brain sets an upper limit on