Abstract

It is a well-known fact that various impossibility theorems show that there is no theory about the value of populations that can satisfy all of the conditions we want to set on such a theory. It is not all clear which condition we should give up, something which many think is especially worrying since in the face of climate change we need to make urgent decisions that will affect the size and composition of future populations. In my previous research, I have tried out two ways of responding to these theorems that do not involve a wholesale rejection of any of the conditions (the evaluative uncertainty approach and the degrees of satisfaction approach). Here I want to take a step back, for it turns out that not everyone is convinced that the impossibility theorems is anything to worry about unless you subscribe to a consequentialist welfarist moral framework. One recent example of this is Samuel Scheffler, who in his book Why worry about future generations (OUP, 2018) argues that in order to determine the reasons we have to care about future people there is no need to construct a population axiology and thus we can simply sidestep the accompanying impossibility theorems. I shall argue that this reflects a serious misunderstanding of population ethics and its impossibility theorems. These theorems are troubling for all reasonable moral views, including Scheffler’s own value of humanity axiology.