Why can't we own people? Boyer proposes that the key consideration concerns inclusion in the moral circle. I propose an alternative, which is that specific mental capacities, especially the capacity for autonomy, play a key role in determining judgments about human and animal ownership. Autonomous beings are viewed as owning themselves, which precludes them from being owned by others.

Recent years have seen a growing interest among psychologists for debates in moral philosophy. Moral psychologists have investigated the causal origins of the opposition between utilitarian and deontological judgments and the psychological underpinnings of people’s beliefs about the moral status of animals. One issue that remains underexplored in this research area is the relationship between people’s disposition to engage in utilitarian thinking and their attitudes towards animals. This gap is unfortunate considering the tight philosophical connection between utilitarianism and the claim (...) that animals have the same moral status as humans. Indeed, the principle of utility leads naturally enough to the view that animals count every bit as much as human beings. In this paper, we report two empirical studies dedicated to bridging this gap. In Study 1, we looked at the relationship between attitudes towards animals and utilitarian judgments in the context of sacrificial dilemmas. In Study 2, we bypassed the problems raised by the use of such dilemmas as a measure of utilitarianism by relying on other types of thought experiments. Overall, our results suggest no strong correlation between utilitarianism and attitudes towards animals. Rather, the existence of a correlation between utilitarianism and attitudes towards animals very much depends on how both are measured. (shrink)

People's treatment of others (humans, nonhuman animals, or other entities) often depends on whether they think the entity is worthy of moral concern. Recent work has begun to investigate which entities are included in a person's moral circle, examining how certain target characteristics (e.g., species category, perceived intelligence) and judge characteristics (e.g., empathy, political orientation) shape moral inclusion. However, the relative importance of target and judge characteristics in predicting moral inclusion remains unclear. When predicting whether a person will deem an (...) entity worthy of moral consideration, how important is it to know who is making the judgment (i.e., characteristics of the judge), who is being judged (i.e., characteristics of the target), and potential interactions between the two factors? Here, we address this foundational question by conducting a variance component analysis of the moral circle. In two studies with participants from the Netherlands, the United States, the United Kingdom, and Australia (N = 836), we test how much variance in judgments of moral concern is explained by between‐target differences, between‐judge differences, and by the interaction between the two factors. We consistently find that all three components explain substantial amounts of variance in judgments of moral concern. Our findings provide two important insights. First, an increased focus on interactions between target and judge characteristics is needed, as these interactions explain as much variance as target and judge characteristics separately. Second, any theoretical account that aims to provide an accurate description of moral inclusion needs to consider target characteristics, judge characteristics, and their interaction. (shrink)