Screening and Regresses

Sometimes a class of evidence can screen off other evidence. That is, sometimes possessing evidence of one kind can make it the case that other facts, facts which would usually be of evidential significance, are not in fact significant. This chapter starts with an argument that many philosophers have assumed that evidence of what one judges screens off the evidential significance of the reasons that judgment is based on. It then argues that these philosophers have gotten things back to front. There is a true principle around here, but it is the other way around: reasons a judgment is based on screens off the evidential significance of that very judgment. I argue this principle must be true, because it is the only motivated way to stop some problematic regresses.

Double Standards

This chapter wraps up three loose ends from the discussion of normative externalism in ethics. It argues that there is nothing wrong with hypocrisy; in any case where hypocritical action seems wrong, some other feature of the act explains the wrongness. It argues that the problem of inter-theoretic value comparisons is not as big a problem for the internalist as is sometimes suggested, since everyone has to solve this problem. And it describes the parts of the bundle of views I call normative externalism, and sets out which of them are more central, or more peripheral, to the bundle.

Akrasia

This chapter argues that epistemic akrasia is rationally permissible. The first task is to describe just what akrasia comes to. Loosely speaking, it is having a belief and thinking one should not have this belief, but there are three importantly different ways to make this precise. Unlike in the previous chapter, there is a systematic reason why none of these will pose a problem to normative externalism. There is no kind of akrasia that is licensed by normative externalism that is not made independently plausible by the failure of evidence to be, in Timothy Williamson’s sense, luminous. All of the arguments against akrasia work equally well, or perhaps we should say equally poorly, as arguments against the luminosity of evidence. The chapter ends with a discussion of the desire as belief arguments, and in particular with an argument that luminosity failures threaten the idea that expected values can be in any way guiding.

Higher-Order Evidence

This chapter discusses higher-order evidence, i.e. evidence directly about the propriety of having some first-order belief. The mainstream position on higher-order evidence is that it can rationally require changes to first-order beliefs. In particular, it is irrational to both believe something, and think that belief is improper in some or other way. The usual argument for this rests on intuitions about cases. I argue that we haven’t considered enough cases, and that there are cases where level-crossing principles give the wrong answer. In particular, the literature has ignored cases where level-crossing principles implausibly imply we should increase our confidence in target propositions. I reconsider the cases that motivated level-crossing principles, and argue that a careful version of evidentialism can explain them.

Level-Crossing Principles

This chapter introduces normative externalism about epistemology. It takes what is central to normative externalism to be the denial of level-crossing principles. A level-crossing principle says there is a necessary connection between the propriety of a belief (in some sense of propriety), and the propriety of believing that very belief to be proper. The main theme of this part is outlined: level-crossing principles are inconsistent with evidentialism, and it is level-crossing principles, not evidentialism, that should be abandoned. The chapter also discusses the relationship between state-level evaluations, like the rationality of a belief, and agent-level evaluations, like the wisdom of a believer. And it briefly discusses the role of evidence in mathematics, and how the kind of evidentialism I favor extends to mathematical belief.

Epilogue

The big theme of the book, that living up to one’s own principles is not intrinsically important, is reviewed. The book ends with a discussion of how the picture of ethics and epistemology we’re left with compares to other ‘tragic’ philosophical views.

Circles, Epistemic and Benign

If we reject level-crossing principles, some apparently circular reasoning becomes licensed. This looks like a problem for normative externalism. This chapter responds to the problem. The response takes some time, because it turns out there are many different ways to understand what it is for reasoning to be circular. The ultimate argument is that for every such way, either it is not problematic, or normative externalism does not license it. But there is no quick proof of this; each way to understand circular reasoning has to be treated separately. The chapter ends with a discussion of the Problem of Easy Knowledge, and of the norms for proper testing of measuring devices.

A Dilemma for Internalism

The previous chapter argued that symmetry between factual and moral ignorance is not ultimately intuitive. This chapter argues that even if it is intuitive, it must be rejected. Or, at least, symmetry between all types of ignorance must be rejected, and without that universal symmetry, symmetry between factual and moral ignorance is not motivated. Universal symmetry must fail because without it we have to say positive things about people who are violating both the correct principles and their own principles, but who think their actions comply with the principles they think they have. After surveying some options, it is argued that there is no plausible positive thing to say about these folks, so symmetry fails.

Disagreement

The following, broadly conciliatory, line on peer disagreement is very popular in current philosophy. In the face of disagreement, we should aggregate everyone’s judgments, and defer to this aggregation. I argue for a new approach. We should aggregate everyone’s reasons, and then form the belief that is rational given those reasons. In short, we should aggregate inputs, i.e. evidence, not outputs. The new approach and the popular approach often agree in practice, but they are very different in theory, and offer very different explanations of why conciliation gets the right results when it does. The chapter starts with some theoretical arguments for conciliatory approaches, and reviews familiar reasons why they fail. It then looks at some examples that are alleged to motivate conciliationism. The evidence aggregation approach can explain these examples, and also explains other examples that conciliationism cannot explain.

Against Symmetry

This chapter argues that there are a host of intuitive asymmetries between moral uncertainty and factual uncertainty, and these are enough to undermine the symmetry-based motivation for internalism. Our reactive attitudes to our own past failings are different if the failings were caused by factual rather than moral ignorance. Factual ignorance can motivate taking a safe but known to be suboptimal outcome; moral ignorance cannot. And unlike factual ignorance, moral ignorance can only lead to bad action if it is paired with a motivation we should not have: namely a motivation to do what is right whatever that is. Various attempts to argue that this is a good motivation are considered and mostly rejected; the attempts that are plausible do not support popular forms of normative internalism.