Abstract
In the Utilitarian tradition of Henry Sidgwick, population ethics is to be considered through the expectation of the sum of utilities of all who are ever born. However, this is unsuited for application to the real world because it takes as its subject the choice to be made by an idealized “objective social planner” and because it takes as its object a theoretical notion of well-being that is derived from no source and bounded by no constraint. In reality, ethical theories must extend into realms of actual decision-makers, who are subjective agents, and well-being, that is derived from consuming the resources of a finite planet. In this paper, we show how it is possible to amend the utilitarian model by altering the way well-beings are aggregated, to reflect the conditions that are faced by those whose decisions have the greatest impact on demographic change, and to combine it with a more realistic notion of well-being, which takes account of the biosphere's ability to supply humanity with goods and services. To demonstrate the flexibility of this model, we put it to work in investigating a critical question of population ethics that classical utilitarianism cannot contend with, how to explain and respond to differential fertility rates around the world. Out model can be used to study a range of phenomena that may lie behind these differences, including different approaches to property rights over natural resources, different ethical assumptions about the value of children, and the unequal distribution of resources. However, we conclude that there are reasons, not simply to let these differences stand, but rather to use ethical insights, from our model and elsewhere, to advocate for changes that are likely to be in the long-term interest of humanity.
This paper was revised and updated in July 2024. You can also read the origional paper published in Studies in Climate Ethics and Future Generations 4
