Andreas Mogensen William MacAskill


It has been argued that evolutionary considerations favour utilitarianism by selectively debunking its competitors. However, evolutionary considerations also seem to undermine the practical significance of utilitarianism, since commonsense beliefs about well-being seem like prime candidates for evolutionary debunking. We argue that the practical significance of utilitarianism is not undermined in this way if we understand the requirements of practical rationality as sensitive to normative uncertainty. We consider the view that rational decision-making under normative uncertainty requires maximizing expected choice-worthiness, as well as the possibility that different theories’ choice-worthiness rankings are not all interval-scale measurable or intertheoretically comparable. Finally, we suggest how evolutionary considerations may increase the practical significance of utilitarianism even if belief in utilitarianism is debunked by evolutionary considerations, so long as belief in competing theories is undermined to an even greater extent.