In Spears (Reference Spears2020) I report empirical survey-experiments that show two patterns. First, many participants report that the promise of a good life counts as a reason to create a child, contrary to the Asymmetry of population ethics. Second, participants’ rejection of the Asymmetry is statistically associated with ‘cognitively reflective’ decision-making. Footnote 1 I am delighted and grateful for Aaron’s (Reference Aaron2022) thoughtful reflections. Aaron raises concerns about the details of the first point (but does not address the second).
Questions like Aaron’s are the normal scientific process in statistical, empirical research. No statistic is ever precisely what you want to know. No questionnaire is perfect. The true fraction of people who would find the Asymmetry plausible upon first encountering it is almost certainly not a number in my paper.
The purpose of my paper was not to use statistics that show that the Asymmetry is false. There were already good arguments that show this. The purpose of my paper was to test the claim that there exists a robust and widely shared intuition that gives credibility to the Asymmetry.
A theme of Aaron’s observations is that my particular survey questions did not capture all of the nuance of the many books and papers about the Asymmetry. Of course, as Aaron agrees, no empirical questionnaire could. And yet, intuition is supposed to come before theory. If so much philosophical sophistication is required to isolate it, is the Asymmetry a pre-theoretical intuition at all? It would be just another scholarly proposition. If the Asymmetry is special, it must be special because it is an intuition that people have.
Here, Aaron and I agree about the most important part. Some people have this intuition and some people don’t. Aaron responds to my statistical study with appropriate questions. People’s intuitive response to the Asymmetry, we agree, is an empirical object subject to social scientific study. Not everybody experiences this intuition, even in the time, place and population that I studied. It is subject to experimental manipulation and observational correlation. I would be excited to read further experiments that test Aaron’s hypotheses, which I think would be feasible.
Whatever those experiments would reveal – whether ¼ or ½ or ¾ of people find the Asymmetry intuitive – support for the Asymmetry is partial, contingent, and, if Aaron is correct, malleable. But alleged intuitiveness is all the Asymmetry has. As Aaron summarizes: ‘Several defences of [the Asymmetry] crucially rely on the supposed intuitiveness … they do not even aim to show that independent premises force us to accept it.’ A squishy intuition alone cannot challenge the fundamental principles of axiology, decision theory and welfare economics. Rationality, anonymity, Pareto, stochastic dominance, non-antiegalitarianism, and rejection of the misanthropic possibility that adding any extra life always makes matters worse: These principles all are supported by intuition robustly, Footnote 2 by strong arguments, and by their coherence with one another. The Asymmetry (although compatible with these individually) conflicts with several combinations of these.
