Derek Parfit presents the third volume of On What Matters, his landmark work of moral philosophy. Parfit develops further his influential treatment of reasons, normativity, the meaning of moral discourse, and the status of morality. He engages with his critics, and shows the way to resolution of their differences.

The 'Evolution of Cooperation' addresses a simple yet age-old question; If living things evolve through competition, how can cooperation ever emerge? Despite the abundant evidence of cooperation all around us, there existed no purely naturalistic answer to this question until 1979, when Robert Axelrod famously ran a computer tournament featuring a standard game-theory exercise called The Prisoner's Dilemma. To everyone's surprise, the program that won the tournament, named Tit for Tat, was not only the simplest but the most "cooperative" entrant. (...) This unexpected victory proved that cooperation - one might even say altruism - is mathematically possible and therefore needs no hidden hand or divine agent to create and sustain it. A great roadblock to the understanding of all sorts of behavior was at last removed. The updated edition includes an extensive new chapter on cooperation in cancer cells and among terrorist organizations. (shrink)

The economic explanation of individual behaviour, even behaviour outside the traditional province of the market, projects a distinctively economic image on the minds of the agents involved. It suggests that, in regard to motivation and rationality, they conform to the profile of homo economicus. But this suggestion, by many lights, flies in the face of common sense; it conflicts with our ordinary assumptions about how we each feel and think in most situations, certainly most non-market situations, and about how that (...) feeling and thought manifests itself in action. What, then, to conclude? That common sense is deeply in error on these matters? That, on the contrary, economics is in error—at least about non-market behaviour—and common sense sound? Or that some form of reconciliation is available between the two perspectives? This paper is an attempt to defend a conciliationist position. (shrink)

Evolutionary debunking arguments are arguments that appeal to the evolutionary origins of evaluative beliefs to undermine their justification. This paper aims to clarify the premises and presuppositions of EDAs—a form of argument that is increasingly put to use in normative ethics. I argue that such arguments face serious obstacles. It is often overlooked, for example, that they presuppose the truth of metaethical objectivism. More importantly, even if objectivism is assumed, the use of EDAs in normative ethics is incompatible with a (...) parallel and more sweeping global evolutionary debunking argument that has been discussed in recent metaethics. After examining several ways of responding to this global debunking argument, I end by arguing that even if we could resist it, this would still not rehabilitate the current targeted use of EDAs in normative ethics given that, if EDAs work at all, they will in any case lead to a truly radical revision of our evaluative outlook. (shrink)

Long claimed to be the dominant conception of practical reason, the Humean theory that reasons for action are instrumental, or explained by desires, is the basis for a range of worries about the objective prescriptivity of morality. As a result, it has come under intense attack in recent decades. A wide variety of arguments have been advanced which purport to show that it is false, or surprisingly, even that it is incoherent. Slaves of the Passions aims to set the record (...) straight, by advancing a version of the Humean theory of reasons which withstands this sophisticated array of objections. Schroeder defends a radical new view which, if correct, means that the commitments of the Humean theory have been widely misunderstood. Along the way, he raises and addresses questions about the fundamental structure of reasons, the nature of normative explanations, the aims of and challenges facing reductive views in metaethics, the weight of reasons, the nature of desire, moral epistemology, and most importantly, the relationship between agent-relational and agent-neutral reasons for action. (shrink)

Ethical concepts are, or purport to be, normative. They make claims on us: they command, oblige, recommend, or guide. Or at least when we invoke them, we make claims on one another; but where does their authority over us - or ours over one another - come from? Christine Korsgaard identifies four accounts of the source of normativity that have been advocated by modern moral philosophers: voluntarism, realism, reflective endorsement, and the appeal to autonomy. She traces their history, showing how (...) each developed in response to the prior one and comparing their early versions with those on the contemporary philosophical scene. Kant's theory that normativity springs from our own autonomy emerges as a synthesis of the other three, and Korsgaard concludes with her own version of the Kantian account. Her discussion is followed by commentary from G. A. Cohen, Raymond Geuss, Thomas Nagel, and Bernard Williams, and a reply by Korsgaard. (shrink)

What is the Moral Problem? NORMATIVE ETHICS VS. META-ETHICS It is a common fact of everyday life that we appraise each others' behaviour and attitudes from ...

Contemporary realist theories of value claim to be compatible with natural science. In this paper, I call this claim into question by arguing that Darwinian considerations pose a dilemma for these theories. The main thrust of my argument is this. Evolutionary forces have played a tremendous role in shaping the content of human evaluative attitudes. The challenge for realist theories of value is to explain the relation between these evolutionary influences on our evaluative attitudes, on the one hand, and the (...) independent evaluative truths that realism posits, on the other. Realism, I argue, can give no satisfactory account of this relation. On the one hand, the realist may claim that there is no relation between evolutionary influences on our evaluative attitudes and independent evaluative truths. But this claim leads to the implausible skeptical result that most of our evaluative judgements are off track due to the distorting pressure of Darwinian forces. The realist’s other option is to claim that there is a relation between evolutionary influences and independent evaluative truths, namely that natural selection favored ancestors who were able to grasp those truths. But this account, I argue, is unacceptable on scientific grounds. Either way, then, realist theories of value prove unable to accommodate the fact that Darwinian forces have deeply influenced the content of human values. After responding to three objections, the third of which leads me to argue against a realist understanding of the disvalue of pain, I conclude by sketching how antirealism is able to sidestep the dilemma I have presented. Antirealist theories of value are able to offer an alternative account of the relation between evolutionary forces and evaluative facts —
an account that allows us to reconcile our understanding of evaluative truth with our understanding of the many non-rational causes that have played a role in shaping our evaluative judgements. (shrink)

This book challenges the view that bad beliefs - beliefs that blatantly conflict with easily available evidence - can largely be explained by widespread irrationality, instead arguing that ordinary people are rational agents whose beliefs are the result of their rational response to the evidence they're presented with.

When the costs of acquiring knowledge outweigh the benefits of possessing it, ignorance is rational. In this paper I clarify and explore a related but more neglected phenomenon: cases in which ignorance is motivated by the anticipated costs of possessing knowledge, not acquiring it. The paper has four aims. First, I describe the psychological and social factors underlying this phenomenon of motivated ignorance. Second, I describe those conditions in which it is instrumentally rational. Third, I draw on evidence from the (...) social sciences to argue that this phenomenon of rational motivated ignorance plays an important but often unappreciated role in one of the most socially harmful forms of ignorance today: voter ignorance of societal risks such as climate change. Finally, I consider how to address the high social costs associated with rational motivated ignorance. (shrink)

The American political landscape exhibits significant polarization. People’s political beliefs cluster around two main camps. However, many of the issues with respect to which these two camps disagree seem to be rationally orthogonal. This feature raises an epistemic challenge for the political partisan. If she is justified in consistently adopting the party line, it must be true that her side is reliable on the issues that are the subject of disagreements. It would then follow that the other side is anti-reliable (...) with respect to a host of orthogonal political issues. Yet, it is difficult to find a psychologically plausible explanation for why one side would get things reliably wrong with respect to a wide range of orthogonal issues. While this project’s empirical discussion focuses on the US context, the argument generalizes to any situation where political polarization exists on a sufficiently large number of orthogonal claims. (shrink)

Changing our minds isn't easy. Even when we recognize our views are disputed by intelligent and informed people, we rarely doubt our rightness. Why is this so? How can we become more open-minded, putting ourselves in a better position to tolerate conflict, advance collective inquiry, and learn from differing perspectives in a complex world? -/- Nathan Ballantyne defends the indispensable role of epistemology in tackling these issues. For early modern philosophers, the point of reflecting on inquiry was to understand how (...) our beliefs are often distorted by prejudice and self-interest, and to improve the foundations of human knowledge. Ballantyne seeks to recover and modernize this classical tradition by vigorously defending an interdisciplinary approach to epistemology, blending philosophical theorizing with insights from the social and cognitive sciences. -/- Many of us need tools to help us think more circumspectly about our controversial views. Ballantyne develops a method for distinguishing between our reasonable and unreasonable opinions, in light of evidence about bias, information overload, and rival experts. This method guides us to greater intellectual openness--in the spirit of skeptics from Socrates to Montaigne to Bertrand Russell--making us more inclined to admit that sometimes we don't have the right answers. With vibrant prose and fascinating examples from science and history, Ballantyne shows how epistemology can help us know our limits. (shrink)

A New York Times Notable Book of 2012 Whether it’s in a cockpit at takeoff or the planning of an offensive war, a romantic relationship or a dispute at the office, there are many opportunities to lie and self-deceive—but deceit and self-deception carry the costs of being alienated from reality and can lead to disaster. So why does deception play such a prominent role in our everyday lives? In short, why do we deceive? In his bold new work, prominent biological (...) theorist Robert Trivers unflinchingly argues that self-deception evolved in the service of deceit—the better to fool others. We do it for biological reasons—in order to help us survive and procreate. From viruses mimicking host behavior to humans misremembering the details of a quarrel, science has proven that the deceptive one can always outwit the masses. But we undertake this deception at our own peril. Trivers has written an ambitious investigation into the evolutionary logic of lying and the costs of leaving it unchecked. (shrink)

Reason, we are told, is what makes us human, the source of our knowledge and wisdom. If reason is so useful, why didn't it also evolve in other animals? If reason is that reliable, why do we produce so much thoroughly reasoned nonsense? In their groundbreaking account of the evolution and workings of reason, Hugo Mercier and Dan Sperber set out to solve this double enigma. Reason, they argue with a compelling mix of real-life and experimental evidence, is not geared (...) to solitary use, to arriving at better beliefs and decisions on our own. What reason does, rather, is help us justify our beliefs and actions to others, convince them through argumentation, and evaluate the justifications and arguments that others address to us. In other words, reason helps humans better exploit their uniquely rich social environment. This interactionist interpretation explains why reason may have evolved and how it fits with other cognitive mechanisms. It makes sense of strengths and weaknesses that have long puzzled philosophers and psychologists--why reason is biased in favor of what we already believe, why it may lead to terrible ideas and yet is indispensable to spreading good ones.--. (shrink)

The economic explanation of individual behaviour, even behaviour outside the traditional province of the market, projects a distinctively economic image on the minds of the agents involved. It suggests that, in regard to motivation and rationality, they conform to the profile of homo economicus. But this suggestion, by many lights, flies in the face of common sense; it conflicts with our ordinary assumptions about how we each feel and think in most situations, certainly most non-market situations, and about how that (...) feeling and thought manifests itself in action. What, then, to conclude? That common sense is deeply in error on these matters? That, on the contrary, economics is in error—at least about non-market behaviour—and common sense sound? Or that some form of reconciliation is available between the two perspectives? This paper is an attempt to defend a conciliationist position. (shrink)

People are biased toward beliefs that are welcomed by their in-group. Some beliefs produced by these biases—such as climate change denial and religious belief—can be fruitfully modeled by signaling theory. The idea is that the beliefs function so as to be detected by others and manipulate their behavior, primarily for the benefits that accrue from favorable tribal self-presentation. Signaling theory can explain the etiology, distinctive form, proper function, and alterability of these beliefs.

Beliefs serve at least two broad functions. First, they help us navigate the world. Second, they serve as signals to manipulate others. Philosophers and psychologists have focused on the first function while largely overlooking the second. This article advances a conception of signals and makes a prima facie case for a social signaling function for at least some beliefs. Truth and rational support are often irrelevant to the signaling function. If some beliefs evolved for a signaling function, then we should (...) expect various biases that aid in the manipulation of others. (shrink)

This is the second volume of a major new work in moral philosophy. It starts with critiques of Derek Parfit's work by four eminent moral philosophers, and his responses. The largest part of the volume is a self-contained monograph on normativity. The final part comprises seven new essays on Kant, reasons, and why the universe exists.