This is a review of Christopher Peacocke's book The Realm of Reason (Oxford University Press, 2004).

What follows is a taxonomy of arguments that regresses of inferential justification are vicious. They fall out into four general classes: conceptual arguments from incompleteness, conceptual arguments from arbitrariness, ought-implies-can arguments from human quantitative incapacities, and ought-implies can arguments from human qualitative incapacities. They fail with a developed theory of "infinitism" consistent with valuational pluralism and modest epistemic foundationalism.

Knowledge and its Limits presents a systematic new conception of knowledge as a kind of mental stage sensitive to the knower's environment. It makes a major contribution to the debate between externalist and internalist philosophies of mind, and breaks radically with the epistemological tradition of analyzing knowledge in terms of true belief. The theory casts new light on such philosophical problems as scepticism, evidence, probability and assertion, realism and anti-realism, and the limits of what can be known. The arguments are (...) illustrated by rigorous models based on epistemic logic and probability theory. The result is a new way of doing epistemology and a notable contribution to the philosophy of mind. (shrink)

Introduction As the title indicates, the chief focus of this book is epistemic justification. But just what is epistemic justification and what is its place ...

This paper further develops the non-restrictive dialectical perspective. Many philosophers hold that truthfulness is somehow constitutive of assertion. I argue against this view while simultaneously attempting to ground truthfulness in assertion’s essential features. I argue that truthfulness is the prima facie best way to avoid decisive counter-arguments against what one says. Moreover, avoiding decisive counter-arguments is a constitutive goal of rational dialectic. Thus, while truthfulness is not constitutive of assertion, it is the rational default strategy for achieving a goal that (...) is constitutive of assertion. (shrink)

The Realm of Reason develops a new, general theory of what it is for a thinker to be entitled to form a given belief. The theory locates entitlement in the nexus of relations between truth, content, and understanding. Peacocke formulates three principles of rationalism that articulate this conception. The principles imply that all entitlement has a component that is justificationally independent of experience. The resulting position is thus a form of rationalism, generalized to all kinds of content. To show how (...) these principles are realized in specific domains, Peacocke applies the theory in detail to several classical problems of philosophy, including the nature of perceptual entitlement, induction, and the status of moral thought. These discussions involve an elaboration of the structure of entitlement in ways that have applications in many other areas of philosophy. He also relates the theory to classical and recent rationalist thought, and to current issues in the theory of meaning, reference and explanation. In the course of these discussions, he proposes a general theory of the a priori. The focus of the work lies in the intersection of epistemology, metaphysics, and the theory of meaning, and will be of interest both to students and researchers in these areas, and to anyone concerned with the idea of rationality. (shrink)

Consider the skeptic about the external world. Let’s straightaway concede to such a skeptic that perception gives us no conclusive or certain knowledge about our surroundings. Our perceptual justification for beliefs about our surroundings is always defeasible—there are always possible improvements in our epistemic state which would no longer support those beliefs. Let’s also concede to the skeptic that it’s metaphysically possible for us to have all the experiences we’re now having while all those experiences are false. Some philosophers dispute (...) this, but I do not. The skeptic I want to consider goes beyond these familiar points to the much more radical conclusion that our perceptual experiences can’t give us any knowledge or even justification for believing that our surroundings are one way rather than another. (shrink)

1. It seems plausible to say that a language is a system of expressions the use of which is subject to certain rules. It would seem, thus, that learning to use a language is learning to obey the rules for the use of its expressions. However, taken as it stands, this thesis is subject to an obvious and devastating refutation. After formulating this refutation, I shall turn to the constructive task of attempting to restate the thesis in a way which (...) avoids it. In doing so, I shall draw certain distinctions the theoretical elaboration of which will, I believe, yield new insight into the psychology of language and of what might be called “norm conforming behavior” generally. The present paper contains an initial attempt along these lines. (shrink)

We commonly speak of people as being ‘‘justified’’ or ‘‘unjustified’’ in believing as they do. These terms describe a person’s epistemic condition. To be justified in believing as one does is to have a positive epistemic status in virtue of holding one’s belief in a way which fully satisfies the relevant epistemic requirements or norms. This requires something more (or other) than simply believing a proposition whose truth is well-supported by evidence, even by evidence which one possesses oneself, since one (...) could entirely miss the relevance of this evidence and hold the belief as a result of wishful thinking or for some other bad reason. My topic in this paper is the notion of being justified which precludes beliefs flawed in this way. I will take the notion of something’s telling in favor of the truth of a proposition—that is, the notion of evidential support—for granted. (shrink)

In this book Jonathan Adler offers a strengthened version of evidentialism, arguing that the ethics of belief should be rooted in the concept of belief--that...

Practical Reason and Norms focuses on three problems: In what way are rules normative, and how do they differ from ordinary reasons? What makes normative systems systematic? What distinguishes legal systems, and in what consists their normativity? All three questions are answered by taking reasons as the basic normative concept, and showing the distinctive role reasons have in every case, thus paving the way to a unified account of normativity. Rules are a structure of reasons to perform the required act (...) and an exclusionary reason not to follow some competing reasons. Exclusionary reasons are explained, and used to unlock the secrets of orders, promises, and decisions as well as rules. Games are used to exemplify normative systems. Inevitably, the analysis extends to some aspects of normative discourse, which is truth-apt, but with a diminished assertoric force. (shrink)

The fundamental question of the ethics of belief is "What ought one to believe?" According to the traditional view of evidentialism, the strength of one's beliefs should be proportionate to the evidence. Conventional ways of defending and challenging evidentialism rely on the idea that what one ought to believe is a matter of what it is rational, prudent, ethical, or personally fulfilling to believe. Common to all these approaches is that they look outside of belief itself to determine what one (...) ought to believe. In this book Jonathan Adler offers a strengthened version of evidentialism, arguing that the ethics of belief should be rooted in the concept of belief—that evidentialism is belief's own ethics. A key observation is that it is not merely that one ought not, but that one cannot, believe, for example, that the number of stars is even. The "cannot" represents a conceptual barrier, not just an inability. Therefore belief in defiance of one's evidence (or evidentialism) is impossible. Adler addresses such questions as irrational beliefs, reasonableness, control over beliefs, and whether justifying beliefs requires a foundation. Although he treats the ethics of belief as a central topic in epistemology, his ideas also bear on rationality, argument and pragmatics, philosophy of religion, ethics, and social cognitive psychology. (shrink)

This essay argues that the Pyrrhonian regress argument presupposes a Prior Grounding conception of justification. This is contrasted with a Default and Challenge structure, which leads to a contextualist picture of justification. Contextualism is said to incorporate the best features of its traditionalist rivals — foundationalism and coherentism — and also to avoid skepticism. It is argued that we should not ask which conception is really true, but instead give up epistemological realism.