A compact, coherent introduction to the study of rational belief, this text provides points of entry to such areas of philosophy as theory of knowledge, methodology of science, and philosophy of language. The book is accessible to all undergraduates and presupposes no philosophical training.

In the middle of the 1980s, logical tools were discovered that make it possible to model changes in belief and knowledge in entirely new ways. These logical tools turned out to be applicable both to human beliefs and to the contents of databases. This is the first textbook in this new area. It contains both discursive chapters with a minimum of formalism and formal chapters in which proofs and proof methods are presented. By using different selections from the formal (...) section the book can be used on all levels of University education. (shrink)

This book gives a general theory of rational belief. Although it can be read by itself, is a sequel to the author's previous book The Value of Rationality (Oxford, 2017). It takes the general conception of rationality that was defended in that earlier book, and combines it with an account of the varieties of belief, and of what it is for these beliefs to count as "correct", to develop an account of what it is for beliefs to count (...) as rational. According to this account, rationality comes in degrees: the degree to which one's beliefs counts as rational is determined by their distance from a corresponding probability function - where this distance is measured by those beliefs' "expected degree of incorrectness" according to the probability function; the account also involves an explanation of what determines exactly which probability function plays this role in each case, and of why this probability function should play this role. In developing and defending this account, new light is shed on several central epistemological issues. These issues include: the distinction between propositional and doxastic justification; the debates between internalism and externalism, and between foundationalism and coherentism; the significance - or lack of it - of the notion of 'evidence'; the relationship between credences, full belief, inference, and suspension of judgment; the nature of the kind of possibility that is presupposed by the relevant sort of probability; and whether rationality is "diachronic" - so that the beliefs that it is rational for us to have now depend, in part, on the beliefs that we held in the past. Finally, some suggestions are made about how this theory bears on a range of further topics, including the defeasibility of inference, scepticism, and the analysis of knowledge. (shrink)

Inspired by the work of Wilfrid Sellars, Michael Williams launches an all-out attack on what he calls "phenomenalism," the idea that our knowledge of the world rests on a perceptual or experiential foundation.

Michael G. Titelbaum presents a new Bayesian framework for modeling rational degrees of belief—the first of its kind to represent rational requirements on agents who undergo certainty loss.

Is a belief that one will succeed necessary for an intention? It is argued that the question has traditionally been badly posed, framed as it is in terms of all-out belief. We need instead to ask about the relation between intention and partial belief. An account of partial belief that is more psychologically realistic than the standard credence account is developed. A notion of partial intention is then developed, standing to all-out intention much as partial (...) class='Hi'>belief stands to all-out belief. Various coherence constraints on the notion are explored. It is concluded that the primary relations between intention and belief should be understood as normative and not essential. (shrink)

This chapter argues that evolutionary debunking arguments are dialectically ineffective. Such arguments rely on the premise that moral judgements can be given evolutionary explanations which do not invoke their truth. The challenge for the debunker is to bridge the gap between this premise and the conclusion that moral judgements are unjustified. After discussing older attempts to bridge this gap, this chapter focuses on Joyce’s recent attempt, which claims that ‘we do not have a believable account of how moral facts could (...) explain the mechanisms…which give rise to moral judgements’. It argues that whether there is such an account depends on what it is permissible to assume about moral truth and that it is reasonable to make assumptions which allow for the possibility of at least partial moral epistemologies. The challenge for the debunker is to show that these assumptions are unreasonable in a way which does not render their debunking argument superfluous. (shrink)

Degrees of belief are familiar to all of us. Our confidence in the truth of some propositions is higher than our confidence in the truth of other propositions. We are pretty confident that our computers will boot when we push their power button, but we are much more confident that the sun will rise tomorrow. Degrees of belief formally represent the strength with which we believe the truth of various propositions. The higher an agent’s degree of belief (...) for a particular proposition, the higher her confidence in the truth of that proposition. For instance, Sophia’s degree of belief that it will be sunny in Vienna tomorrow might be .52, whereas her degree of belief that the train will leave on time might be .23. The precise meaning of these statements depends, of course, on the underlying theory of degrees of belief. These theories offer a formal tool to measure degrees of belief, to investigate the relations between various degrees of belief in different propositions, and to normatively evaluate degrees of belief. (shrink)

Rejecting the category of belief is one of the most striking and profound ideas to emerge from the ontological turn. This essay will argue that the rejection of belief is best understood as part of a broader rejection of representationalism. Representationalism regards thought, speech, and intentionality as depending primarily on the mind’s ability to manipulate beliefs, ideas, meanings, or similar contents. Some central strands of the ontological turn thus participate in the philosophical project of understanding human life without (...) appeal to such representational states. After showing how 20th century anthropology was implicated in the representationalist picture, this essay will critique some of the arguments against belief found among proponents of the ontological turn. It will then try to construct a more robust argument against the use of the category of belief in anthropology. It ends with some reflections on what it means to do anthropology without belief. (shrink)

This essay presents a philosophical and computationol theory of the representation of de re, de dlcto, nested, and quasi-indexical belief reports expressed in natural language. The propositional Semantic Network Processing System (SNePS) is used for representing and reasoning about these reports. In particular, quasi-indicators (indexical expressions occurring in intentional contexts and representing uses of indicators by another speaker) pose problems for natural language representation and reasoning systems, because--unlike pure indicators --they cannot be replaced by coreferential NPs without changing the (...) meaning of the embedding sentence. Therefore, the referent of the quasi-indicator must be represented in such a way that no invalid coreferential claims are entailed. The importance of quasi-indicators is discussed, and it is shown that all four of the above categories of belief reports can be handled by a single representational technique using belief spaces containing intensional entities. Inference rules and belief-revision techniques for the system are also examined. (shrink)