Are we living at the hinge of history?

William MacAskill (Global Priorities Institute, Oxford University)

GPI Working Paper No. 12-2020, published in Ethics and Existence: The Legacy of Derek Parfit

In the final pages of On What Matters, Volume II, Derek Parfit comments: ‘We live during the hinge of history... If we act wisely in the next few centuries, humanity will survive its most dangerous and decisive period... What now matters most is that we avoid ending human history.’ This passage echoes Parfit's comment, in Reasons and Persons, that ‘the next few centuries will be the most important in human history’.

But is the claim that we live at the hinge of history true? The argument of this paper is that it is not. The paper first suggests a way of making the hinge of history claim precise and action-relevant in the context of the question of whether altruists should try to do good now, or invest their resources in order to have more of an impact later on. Given this understanding, there are two worldviews - the Time of Perils and Value Lock-in views - on which we are indeed living during, or about to enter, the hinge of history.

This paper then presents two arguments against the hinge of history claim: first, that it is a priori extremely unlikely to be true, and that the evidence in its favour is not strong enough to overcome this a priori unlikelihood; second, an inductive argument that our ability to influence events has been increasing over time, and we should expect that trend to continue into the future. The paper concludes by considering two additional arguments in favour of the claim, and suggests that though they have some merit, they are not sufficient for us to think that the present time is the most important time in the history of civilisation.

Other working papers

The scope of longtermism – David Thorstad (Global Priorities Institute, University of Oxford)

Longtermism holds roughly that in many decision situations, the best thing we can do is what is best for the long-term future. The scope question for longtermism asks: how large is the class of decision situations for which longtermism holds? Although longtermism was initially developed to describe the situation of…

High risk, low reward: A challenge to the astronomical value of existential risk mitigation – David Thorstad (Global Priorities Institute, University of Oxford)

Many philosophers defend two claims: the astronomical value thesis that it is astronomically important to mitigate existential risks to humanity, and existential risk pessimism, the claim that humanity faces high levels of existential risk. It is natural to think that existential risk pessimism supports the astronomical value thesis. In this paper, I argue that precisely the opposite is true. Across a range of assumptions, existential risk pessimism significantly reduces the value of existential risk mitigation…

Three mistakes in the moral mathematics of existential risk – David Thorstad (Global Priorities Institute, University of Oxford)

Longtermists have recently argued that it is overwhelmingly important to do what we can to mitigate existential risks to humanity. I consider three mistakes that are often made in calculating the value of existential risk mitigation: focusing on cumulative risk rather than period risk; ignoring background risk; and neglecting population dynamics. I show how correcting these mistakes pushes the value of existential risk mitigation substantially below leading estimates, potentially low enough to…