David Mokriski

According to the conciliatory view in metaontology, there are multiple possible languages corresponding to the popular positions in ontology. In each of these languages, the term ‘exists’ expresses a distinct “existence-like” property, and consequently the claims associated with each of the rival ontological positions come out true in some such language. Species of the conciliatory view can be distinguished based on claims about how the various existence-like properties are related vis-à-vis metaphysical naturalness. On some versions, all of the existence-like properties are held to be equally natural, such that there is no “metaphysically privileged” language. However on others, there is held to be a most natural existence-like property and hence a most fundamental ontological language. In this paper I defend two views, one metaontological and one ontological. I first defend a version of the conciliatory view according to which there is exactly one perfectly natural existence-like property, but the rest are still “reasonably” natural. I then argue that, assuming this metaontological view, we should accept a permissive ontological view in the fundamental language (i.e. one with a very expansive domain).

The Moral Twin Earth challenge to ethical naturalism threatens to undermine an otherwise promising metaethical view by showing that typical, naturalist-friendly theories of reference determination predict diverging reference in Twin Earth scenarios, making it difficult to account for substantive moral disagreement. Several theorists have recently invoked David Lewis’s doctrine of reference magnetism as a solution, claiming that a highly elite moral property—a moral “joint in nature”—could secure shared reference between ourselves and our twins on Twin Earth, despite our diverging usages of moral terms. This paper argues that this move has significant methodological implications: namely, it entails that a certain sort of simplicity is truth-conducive. Consequently, when applied to moral theories, this gives certain views, specifically monist ones like utilitarianism and contractualism, an advantage over their more complicated rivals, forms of pluralism and particularism. Thus, ethical naturalists cannot invoke reference magnetism without a substantial impact on first-order theorizing.

According to the eligibility theory of meaning, often attributed to David Lewis, the referent of a predicate is the property that best balances the twin constraints of charity and eligibility, where eligibility is a function of metaphysical naturalness. This sort of metasemantics, which is motivated by its ability to resolve problems of indeterminacy and secure shared reference between disputing parties, can be somewhat friendly towards revisionary theories, since highly natural properties can act as “reference magnets,” securing our reference despite some mismatch with usage. In this paper, I apply these considerations to normative ethics and argue that the theory of rule utilitarianism achieves a high balance of charity and eligibility. I proceed by comparing rule utilitarianism to two of its well-known rivals, act utilitarianism and Rossian pluralism. I show how the former achieves a high degree of eligibility but only at a significant cost of charity, while the latter does the opposite, fitting very nicely with our considered judgments but at the price of very low eligibility. Rule utilitarianism, on the other hand, strikes a good balance between these extremes; it assigns to our core moral term a relatively natural property without doing too much damage to our moral convictions. Thus, rule utilitarianism should be regarded as a promising moral theory by any philosopher who takes seriously considerations of eligibility and naturalness.