This is a major work in moral philosophy, the long-awaited follow-up to Parfit's 1984 classic Reasons and Persons, a landmark of twentieth-century philosophy. Parfit now presents a powerful new treatment of reasons and a critical examination of the most prominent systematic moral theories, leading to his own ground-breaking conclusion.

We are reliable about logic in the sense that we by-and-large believe logical truths and disbelieve logical falsehoods. Given that logic is an objective subject matter, it is difficult to provide a satisfying explanation of our reliability. This generates a significant epistemological challenge, analogous to the well-known Benacerraf-Field problem for mathematical Platonism. One initially plausible way to answer the challenge is to appeal to evolution by natural selection. The central idea is that being able to correctly deductively reason conferred a (...) heritable survival advantage upon our ancestors. However, there are several arguments that purport to show that evolutionary accounts cannot even in principle explain how it is that we are reliable about logic. In this paper, I address these arguments. I show that there is no general reason to think that evolutionary accounts are incapable of explaining our reliability about logic. (shrink)

I believe that Tom is the proud father of a baby boy. Why do I think his child is a boy? A natural answer might be that I remember that his name is ‘Owen’ which is usually a boy’s name. Here I’ve given information that might be part of a causal explanation of my believing that Tom’s baby is a boy. I do have such a memory and it is largely what sustains my conviction. But I haven’t given you just (...) any causally relevant information, I’ve given my grounds for my belief. I’ve given reasons that might justify me in supposing that Tom’s baby is a boy. Less naturally, the question might be taken as a request for a broader causal explanation of my holding this belief. Appropriate answers might cite all manner of facts concerning the evolution of the human race, why I chose to pursue philosophy and hence came to know Tom, the mechanisms of email transmission, the firing of various neurons, the circumstances of concept formation as a result of which I’m able to grasp the thought that Tom’s baby is a boy, and so on. It is an interesting question what distinguishes the narrower set of answers that I first suggested. I won’t pursue that here. I assume you have a good enough sense of the distinction I’m drawing. We might call the narrower set of answers justifying reasons, the kind of reasons I might cite in justifying my belief. Answers of the first sort are clearly relevant to epistemological evaluation. In assessing whether you know p or are rational in believing it to the degree you do, I will naturally want to consider what reasons you have for your belief. In deliberating myself about whether to believe p, in seeking an answer to the question of whether p, I will naturally consider what reasons or grounds I have to suppose that p. But what I want to focus on here is how explanations of the broader sort bear on such questions as whether to believe p. From a third-person perspective we can ask, ‘In assessing the epistemic status of S’s belief that p, what is the relevance of causal information that lies outside of the realm of justifying reasons?’ From the first-person standpoint we can ask ‘In seeking to answer whether p, how should such causal information affect my deliberations?’ At first it might seem that such broader causal information could have little relevance if any. Like any belief my belief that p can be traced back to innumerable causes from far and wide.. (shrink)

We think of logic as objective. We also think that we are reliable about logic. These views jointly generate a puzzle: How is it that we are reliable about logic? How is it that our logical beliefs match an objective domain of logical fact? This is an instance of a more general challenge to explain our reliability about a priori domains. In this paper, I argue that the nature of this challenge has not been properly understood. I explicate the challenge (...) both in general and for the particular case of logic. I also argue that two seemingly attractive responses – appealing to a faculty of rational insight or to the nature of concept possession – are incapable of answering the challenge. (shrink)

Evolutionary debunkers of morality hold this thesis: If S’s moral belief that P can be given an evolutionary explanation, then S’s moral belief that P is not knowledge. In this paper, I debunk a variety of arguments for this thesis. I first sketch a possible evolutionary explanation for some human moral beliefs. Next, I explain how, given a reliabilist approach to warrant, my account implies that humans possess moral knowledge. Finally, I examine the debunking arguments of Michael Ruse, Sharon Street, (...) and Richard Joyce. I draw on the account of moral knowledge sketched earlier to illustrate how these arguments fail. -/- . (shrink)

This paper defends moral realism against Sharon Street’s “Darwinian Dilemma for Realist Theories of Value” (this journal, 2006). I argue by separation of cases: From the assumption that a certain normative claim is true, I argue that the first horn of the dilemma is tenable for realists. Then, from the assumption that the same normative claim is false, I argue that the second horn is tenable. Either way, then, the Darwinian dilemma does not add anything to realists’ epistemic worries.

Responding rationally to the information that others disagree with one’s beliefs requires assessing the epistemic credentials of the opposing beliefs. Conciliatory accounts of disagreement flow in part from holding that these assessments must be independent from one’s own initial reasoning on the disputed matter. I argue that this claim, properly understood, does not have the untoward consequences some have worried about. Moreover, some of the difficulties it does engender must be faced by many less conciliatory accounts of disagreement.

Through his S–R model of statistical relevance, Wesley Salmon offers a solution to the scientific explanation of objectively improbable events.

Approaches to explanation -- Causal and explanatory relevance -- The kairetic account of /D making -- The kairetic account of explanation -- Extending the kairetic account -- Event explanation and causal claims -- Regularity explanation -- Abstraction in regularity explanation -- Approaches to probabilistic explanation -- Kairetic explanation of frequencies -- Kairetic explanation of single outcomes -- Looking outward -- Looking inward.

Among theories which fit all of our data, we prefer the simpler over the more complex. Why? Surely not merely for practical convenience or aesthetic pleasure. But how could we be justified in this preference without knowing in advance that the world is more likely to be simple than complex? And isn’t this a rather extravagant a priori assumption to make? I want to suggest some steps we can take toward reducing this embarrassment, by showing that the assumption which supports (...) favouring simplicity is far more modest than it first seems. (shrink)

A response is given here to Benacerraf's 1973 argument that mathematical platonism is incompatible with a naturalistic epistemology. Unlike almost all previous platonist responses to Benacerraf, the response given here is positive rather than negative; that is, rather than trying to find a problem with Benacerraf's argument, I accept his challenge and meet it head on by constructing an epistemology of abstract (i.e., aspatial and atemporal) mathematical objects. Thus, I show that spatio-temporal creatures like ourselves can attain knowledge about mathematical (...) objects by simply explaininghow they can do this. My argument is based upon the adoption of a particular version of platonism — full-blooded platonism — which asserts that any mathematical object which possiblycould exist actuallydoes exist. (shrink)

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 is a defense of modal realism; the thesis that our world is but one of a plurality of worlds, and that the individuals that inhabit our world are only a few out of all the inhabitants of all the worlds. Lewis argues that the philosophical utility of modal realism is a good reason for believing that it is true.

David Enoch develops, argues for, and defends a strongly realist and objectivist view of ethics and normativity more broadly. This view--according to which there are perfectly objective, universal, moral and other normative truths that are not in any way reducible to other, natural truths--is familiar, but this book is the first in-detail development of the positive motivations for the view into reasonably precise arguments. And when the book turns to defend Robust Realism against traditional objections, it mobilizes the original positive (...) arguments for the view to help with fending off the objections. (shrink)

Suppose we grant that evolutionary forces have had a profound effect on the contours of our normative judgments and intuitions. Can we conclude anything from this about the correct metaethical theory? I argue that, for the most part, we cannot. Focusing my attention on Sharon Street’s justly famous argument that the evolutionary origins of our normative judgments and intuitions cause insuperable epistemological difficulties for a metaethical view she calls "normative realism," I argue that there are two largely independent lines of (...) argument in Street’s work which need to be teased apart. The first of these involves a genuine appeal to evolutionary considerations, but it can fairly easily be met by her opponents. The second line of argument is more troubling; it raises a significant problem, one of the most difficult in all of philosophy, namely how to justify our reliance on our most basic cognitive faculties without relying on those same faculties in a question-begging manner. However, evolutionary considerations add little to this old problem, and rejecting normative realism is not a way to solve it. (shrink)

Can we have objective knowledge of right and wrong, of how we should live and what there is reason to do? Can it be anything but luck when our moral beliefs are true? Kieran Setiya confronts these questions in their most compelling and articulate forms, and argues that if there is objective ethical knowledge, human nature is its source.

It is commonly suggested that evolutionary considerations generate an epistemological challenge for moral realism. At first approximation, the challenge for the moral realist is to explain our having many true moral beliefs, given that those beliefs are the products of evolutionary forces that would be indifferent to the moral truth. An important question surrounding this challenge is the extent to which it generalizes. In particular, it is of interest whether the Evolutionary Challenge for moral realism is equally a challenge for (...) mathematical realism. It is widely thought not to be. In this paper, I argue that the Evolutionary Challenge for moral realism is equally a challenge for mathematical realism. Along the way, I substantially clarify the Evolutionary Challenge, discuss its relation to more familiar epistemological challenges, and broach the problem of moral disagreement. The paper should be of interest to ethicists because it places pressure on anyone who rejects moral realism on the basis of the Evolutionary Challenge to reject mathematical realism as well. And the paper should be of interest to philosophers of mathematics because it presents a new epistemological challenge for mathematical realism that bears, I argue, no simple relation to Paul Benacerraf's familiar challenge. (shrink)

Presenting a selection of thirteen essays on various topics at the foundations of philosophy--one previously unpublished and eight accompanied by substantial new postscripts--this book offers outstanding insight on truth, meaning, and propositional attitudes; semantic indeterminacy and other kinds of "factual defectiveness;" and issues concerning objectivity, especially in mathematics and in epistemology. It will reward the attention of any philosopher interested in language, epistemology, or mathematics.

It is notoriously difficult to spell out the norms of inductive reasoning in a neat set of rules. I explore the idea that explanatory considerations are the key to sorting out the good inductive inferences from the bad. After defending the crucial explanatory virtue of stability, I apply this approach to a range of inductive inferences, puzzles, and principles such as the Raven and Grue problems, and the significance of varied data and random sampling.

This disagreement extends to the fundamental details of physical and biochemical theories. On the other hand, (2) There is almostuniversal agreementthatlife did notfirstcome aboutmerely by chance. This is not to say that all scientists think that life’s existence was inevitable. The common view is that given a fuller understanding of the physical and biological conditions and processes involved, the emergence of life should be seen to be quite likely, or at least not very surprising. The view which is almost universally (...) rejected by researchers in the field is that the numerous and prima facie improbable physical and biological requirements for life all fell together just by a fluke, like so many dice tumbling out of a bag and landing all sixes. Most importantly, for the purposes of the following discussion, (3) The conviction that life did not arise largely by chance is treated as epistem- ically prior to the development of alternative theories. C 2007, Copyright the Authors Journal compilation C 2007, Blackwell Publishing, Inc. (shrink)

It has been the dominant view that probabilistic explanations of particular facts must be inductive in character. I argue here that this view is mistaken, and that the aim of probabilistic explanation is not to demonstrate that the explanandum fact was nomically expectable, but to give an account of the chance mechanism(s) responsible for it. To this end, a deductive-nomological model of probabilistic explanation is developed and defended. Such a model has application only when the probabilities occurring in covering laws (...) can be interpreted as measures of objective chance, expressing the strength of physical propensities. Unlike inductive models of probabilistic explanation, this deductive model stands in no need of troublesome requirements of maximal specificity or epistemic relativization. (shrink)

Moderate rationalists maintain that our rational intuitions provide us with prima facie justification for believing various necessary propositions. Such a claim is often criticized on the grounds that our having reliable rational intuitions about domains in which the truths are necessary is inexplicable in some epistemically objectionable sense. In this paper, I defend moderate rationalism against such criticism. I argue that if the reliability of our rational intuitions is taken to be contingent, then there is no reason to think that (...) our reliability is inexplicable. I also suggest that our reliability is, in fact, necessary, and that such necessary reliability neither admits of, nor requires, any explanation of the envisaged sort. (shrink)

Hartry Field; XV*—The A Prioricity of Logic, Proceedings of the Aristotelian Society, Volume 96, Issue 1, 1 June 1996, Pages 359–380, https://doi.org/10.1093/ar.