Tristram McPherson

One class of central debates between normative realists appears to concern whether we should be naturalists or reductionists about the normative. However, metaethical discussion of naturalism and reduction is often inconsistent, murky, or uninformative. This can make it hard to see why commitments relative to these metaphysical categories should matter to normative realists. This paper aims to clarify the nature of these categories, and their significance in debates between normative realists. I develop and defend what I call the joint-carving taxonomy, which builds on David Lewis’ notion of elite properties. I argue that this taxonomy is clear and metaphysically interesting, and answers to distinctive taxonomic interests of normative realists. I also suggest that it has important implications for the project of adjudicating debates among normative realists.

Recently, some philosophers have suggested that a form of robust realism about ethics, or normativity more generally, does not face a significant explanatory burden in metaphysics. I call this view metaphysically quietist normative realism . This paper argues that while this view can appear to constitute an attractive alternative to more traditional forms of normative realism, it cannot deliver on this promise. I examine Scanlon’s attempt to defend such a quietist realism, and argue that rather than silencing metaphysical questions about normative reasons, his defense at best succeeds only in shifting the focus of metaphysical enquiry. I then set aside the details of Scanlon’s view, and argue on general grounds that that the quietist realist cannot finesse a crucial metanormative task: to explain the contrast between the correct normative system and alternative putatively normative standards.

Some philosophers have been attracted to the idea that morality is an autonomous domain. One version of this idea is the thesis that non-moral claims are irrelevant to the justification of fundamental normative ethical theories. However, this autonomy thesis appears to be in tension with a pair of apparent features of metaethical theorizing. On one hand, metaethics seemingly aims to explain how morality fits into our broader conception of the world. On the other, metaethical theorizing appears to have potential normative ethical implications. This apparent tension may help to explain some contemporary worries about metaethics as a philosophical project. This paper examines three responses to this tension. The first response seeks to resolve the tension by claiming that metaethical theories must be neutral between normative ethical theories. The second response seeks to eliminate the tension by appealing to a deep divide between practical and theoretical reasoning. I show that each of these responses would require a radical reconception of metaethics. I argue that such a reconception is not required in order to resolve the apparent tension between metaethics and the autonomy thesis. I show that this tension is merely apparent, and can be dissolved without casting doubt on metaethics as a project. I argue that on the picture that results, whether the autonomy thesis is true itself depends upon metaethical fact.

G. E. Moore famously argued against skepticism and idealism by appealing to their inconsistency with alleged certainties, like the existence of his own hands. Recently, some philosophers have offered analogous arguments against revisionary views about ethics such as metaethical error theory. These arguments appeal to the inconsistency of error theory with seemingly obvious moral claims like “it is wrong to torture an innocent child just for fun.” It might seem that such ‘Moorean’ arguments in ethics will stand or fall with Moore’s own arguments in metaphysics and epistemology, in virtue of their shared structure. I argue that this is not so. I suggest that the epistemic force of the canonical Moorean arguments can best be understood to rest on asymmetries in indirect evidence. I then argue that this explanation suggests that Moorean arguments are less promising in ethics than they are against Moore’s own targets. I conclude by examining the competing attempt to vindicate Moorean arguments by appealing to Rawls’s method of reflective equilibrium

The convergence of computing, sensing, and communication technology will soon permit large-scale deployment of self-driving vehicles. This will in turn permit a radical transformation of traffic control technology. This paper makes a case for the importance of addressing questions of social justice in this transformation, and sketches a preliminary framework for doing so. We explain how new forms of traffic control technology have potential implications for several dimensions of social justice, including safety, sustainability, privacy, efficiency, and equal access. Our central focus is on efficiency and equal access as desiderata for traffic control design. We explain the limitations of conventional traffic control in meeting these desiderata, and sketch a preliminary vision for a next-generation traffic control tailored to address better the demands of social justice. One component of this vision is cooperative, hierarchically distributed self-organization among vehicles. Another component of this vision is a priority system enabling selection of priority levels by the user for each vehicle trip in the network, based on the supporting structure of non-monetary credits.

Ethical non-naturalists often charge that their naturalist competitors cannot adequately explain the distinctive normativity of moral or more broadly practical concepts. I argue that the force of the charge is mitigated, because non-naturalism is ultimately committed to a kind of mysterianism about the metaphysics of practical norms that possesses limited explanatory power. I then show that focusing on comparative judgments about the explanatory power of various metaethical theories raises additional problems for the non-naturalist, and suggest grounds for optimism that a naturalistic realist about practical normativity will ultimately be able to explain the distinctive normativity of practical norms. I then show that radical pluralism or particularism about the structure of normative ethics would complicate the naturalistic strategy that I defend. This suggests a perhaps surprising way in which the resolution of the debate between ethical naturalists and non-naturalists may rest in part on the answers to substantive normative questions.