Abstract
According to the Asymmetry, adding lives that are not worth living to the population makes the outcome pro tanto worse, but adding lives that are well worth living to the population does not make the outcome pro tanto better. It has been argued that the Asymmetry entails the desirability of human extinction. However, this argument rests on a misunderstanding of the kind of neutrality attributed to the addition of lives worth living by the Asymmetry. A similar misunderstanding is shown to underlie Benatar’s case for anti-natalism.
Introduction
In the final section of the last book that he published in his lifetime, Derek Parfit (2011: 920-5) turned his attention to posterity. True to form, his thoughts were not on his own legacy, but on the value of all future history. No doubt, the centuries and millennia to come will be horrible in many ways, just as the past has been. People will continue to suffer and despair. But people will also experience love and joy and contentment. Will the good be sufficient to outweigh the bad? Will it all be worth it? Parfit’s discussion is brief and inconclusive, but leans toward ‘Yes’.
One might believe that this is ultimately an empirical question to which philosophers have little to contribute. However, there are some philosophical theories, like the Asymmetry in population ethics, which may seem to allow us to settle the question from the armchair.
There are different ways in which the Asymmetry can be formulated, depending on whether it is assumed to be a thesis about moral reasons (McMahan 1981), moral obligations (Roberts 2011), or moral value (Holtug 2004). Exactly how these different formulations of the Asymmetry relate to one another will depend on what relationships obtain between reasons, obligations, and goodness. I take no stand on this issue. In this paper, I focus exclusively on the axiological formulation of the Asymmetry: the view that whereas adding lives that are not worth living to the population makes the outcome pro tanto worse, adding lives that are well worth living to the population does not make the outcome pro tanto better (or worse).
Holtug (2004) argues that the Asymmetry (so understood) speaks in favour of extinction. He asks us to imagine that we can either choose to carry on the human race or let it go extinct by having no children. For simplicity, we assume that we ourselves are equally happy with either choice. The Asymmetry entails that it would be better for us to allow the human race to go extinct, Holtug claims, “because, among the billions of people they could cause to exist, there would surely be a few … who would be miserable; and while their misery would count against their being created, the happiness of the rest would count for nothing.” (139)
Holtug is mistaken to draw this inference. The axiological formulation of the Asymmetry does not entail that extinction would be better than carrying on, even granting that there will be some people whose lives will be miserable and many whose lives will be worth living but whose addition to the population is neutral in value. This follows only if we assume that a bad thing plus a neutral thing adds up to a bad thing. However, it is well-known that those who defend the Asymmetry have powerful independent reasons to reject this principle and posit that the neutrality of additional good lives can be ‘greedy’, i.e., “able to swallow up bad things and neutralize them.” (Broome 2005: 409) Similar observations undermine Benatar’s case for anti-natalism (Benatar 2006).
