Predictable polarization is everywhere: we can often predict how people’s opinions, including our own, will shift over time. Extant theories either neglect the fact that we can predict our own polarization, or explain it through irrational mechanisms. They needn’t. Empirical studies suggest that polarization is predictable when evidence is ambiguous, that is, when the rational response is not obvious. I show how Bayesians should model such ambiguity and then prove that—assuming rational updates are those which obey the value (...) of evidence—ambiguity is necessary and sufficient for the rationality of predictable polarization. The main theoretical result is that there can be a series of such updates, each of which is individually expected to make you more accurate, but which together will predictably polarize you. Polarization results from asymmetric increases in accuracy. This mechanism is not only theoretically possible, but empirically plausible. I argue that cognitive search—searching a cognitively accessible space for a particular item—often yields asymmetrically ambiguous evidence, I present an experiment supporting its polarizing effects, and I use simulations to show how it can explain two of the core causes of polarization: confirmation bias and the group polarization effect. (shrink)

This is a paperback edition of a major contribution to the field, first published in hard covers in 1977. The book outlines a general theory of rational behaviour consisting of individual decision theory, ethics, and game theory as its main branches. Decision theory deals with a rational pursuit of individual utility; ethics with a rational pursuit of the common interests of society; and game theory with an interaction of two or more rational individuals, each pursuing his (...) own interests in a rational manner. (shrink)

Scott Sturgeon presents an original account of mental states and their dynamics. He develops a detailed story of coarse- and fine-grained mental states, a novel perspective on how they fit together, an engaging theory of the rational transitions between them, and a fresh view of how formal methods can advance our understanding in this area. In doing so, he addresses a deep four-way divide in literature on epistemic rationality. Formal epistemology is done in specialized languages--often seeming a lot more (...) like mathematics than Plato--and so can alienate philosophers who are drawn to more traditional work on thought experiments in epistemic rationality. Conversely, informal epistemology appears to be a lot more like Plato than mathematics and, as such, it tends to deter philosophers drawn to formal models of the phenomena. Similarly, the epistemology of coarse-grained states boils down everything to a discussion of rational belief--making the area appear a lot more like foundations of knowledge than anything useful for the theory rational decision, such as decision-making under uncertainty. The Rational Mind unifies work in all of these areas for the first time. (shrink)

Closure for justification is the claim that thinkers are justified in believing the logical consequences of their justified beliefs, at least when those consequences are competently deduced. Many have found this principle to be very plausible. Even more attractive is the special case of Closure known as Single-Premise Closure. In this paper, I present a challenge to Single-Premise Closure. The challenge is based on the phenomenon of rational self-doubt – it can be rational to be less than fully (...) confident in one's beliefs and patterns of reasoning. In rough outline, the argument is as follows: Consider a thinker who deduces a conclusion from a justified initial premise via an incredibly long sequence of small competent deductions. Surely, such a thinker should suspect that he has made a mistake somewhere. And surely, given this, he should not believe the conclusion of the deduction even though he has a justified belief in the initial premise. (shrink)

According to Bayesian epistemology, rational learning from experience is consistent learning, that is learning should incorporate new information consistently into one's old system of beliefs. Simon M. Huttegger argues that this core idea can be transferred to situations where the learner's informational inputs are much more limited than Bayesianism assumes, thereby significantly expanding the reach of a Bayesian type of epistemology. What results from this is a unified account of probabilistic learning in the tradition of Richard Jeffrey's 'radical probabilism'. (...) Along the way, Huttegger addresses a number of debates in epistemology and the philosophy of science, including the status of prior probabilities, whether Bayes' rule is the only legitimate form of learning from experience, and whether rational agents can have sustained disagreements. His book will be of interest to students and scholars of epistemology, of game and decision theory, and of cognitive, economic, and computer sciences. (shrink)

We ordinarily suppose that there is a difference between having and failing to exercise a rational capacity on the one hand, and lacking a rational capacity altogether on the other. This is crucial for our allocations of responsibility. Someone who has but fails to exercise a capacity is responsible for their failure to exercise their capacity, whereas someone who lacks a capacity altogether is not. However, as Gary Watson pointed out in his seminal essay ’Skepticism about Weakness of (...) Will’, the idea of an unexercised capacity is much more difficult to make sense of than it initially appears. The aim of ’Rational Capacities’ is to provide the needed explication of this idea. (shrink)

In past years, the traditional Bayesian theory of rational decision making, based on subjective calculations of expected utility, has faced powerful attack from philosophers such as David Lewis and Brian Skyrms, who advance an alternative causal decision theory. The test they present for the Bayesian is exemplified in the decision problem known as 'Newcomb's paradox' and in related decision problems and is held to support the prescriptions of the causal theory. As well as his conclusions, the concepts and methods (...) of Professor Eells introduces in the course of his analyses have extensive implications, not solely for probability theorists narrowly conceived, but for economists, statisticians and psychologists concerned with decision making and the employment of Bayesian principles. They and their students will, in addition, find the early chapters of great use as a background and introduction to the subject as a whole. (shrink)

It is widely held that Bayesian decision theory is the final word on how a rational person should make decisions. However, Leonard Savage--the inventor of Bayesian decision theory--argued that it would be ridiculous to use his theory outside the kind of small world in which it is always possible to "look before you leap." If taken seriously, this view makes Bayesian decision theory inappropriate for the large worlds of scientific discovery and macroeconomic enterprise. When is it correct to use (...) Bayesian decision theory--and when does it need to be modified? Using a minimum of mathematics, Rational Decisions clearly explains the foundations of Bayesian decision theory and shows why Savage restricted the theory's application to small worlds. The book is a wide-ranging exploration of standard theories of choice and belief under risk and uncertainty. Ken Binmore discusses the various philosophical attitudes related to the nature of probability and offers resolutions to paradoxes believed to hinder further progress. In arguing that the Bayesian approach to knowledge is inadequate in a large world, Binmore proposes an extension to Bayesian decision theory--allowing the idea of a mixed strategy in game theory to be expanded to a larger set of what Binmore refers to as "muddled" strategies. Written by one of the world's leading game theorists, Rational Decisions is the touchstone for anyone needing a concise, accessible, and expert view on Bayesian decision making. (shrink)

According to the author of "After Virtue, " to flourish, humans need to develop virtues of independent thought and acknowledged social dependence. This book presents the moral philosopher's comparison of humans to other animals and his exploration of the impact of these virtues.

Perceptual experience usually comes with “phenomenal force”, a strong sense that it reflects reality as it is. Some philosophers have argued that it is in virtue of possessing phenomenal force that perceptual experiences are able to non‐inferentially justify beliefs. In this article, I introduce an alternative, inferentialist take on the epistemic role of phenomenal force. Drawing on Bayesian modeling in cognitive science, I argue that the sense of reality that accompanies conscious vision can be viewed as epistemically appraisable in light (...) of its rational etiology. (shrink)

This Volume contains seven works of Kant, newly translated and edited, with Introductions. What does it mean to orient oneself in thinking? 1786 (Allen Wood) On the miscarriage of all philosophical trials in theodicy. 1791 (George di Giovanni Religion within the boundaries of mere reason. 1793 (George di Giovanni) The end of all things. 1794 (Allen Wood) The conflict of the faculties. 1798 (Mary J. Gregor & Robert Anchor) Preface to Reinhold Bernhard Jackmann's examination of the Kantian Philosophy of Religion. (...) 1800 (Allen W. Wood) Lectures on the philosophical doctrines of religion (1817) (Allen W. Wood -/- . (shrink)

Real-world agents do not know all consequences of what they know. But we are reluctant to say that a rational agent can fail to know some trivial consequence of what she knows. Since every consequence of what she knows can be reached via chains of trivial cot be dismissed easily, as some have attempted to do. Rather, a solution must give adequate weight to the normative requirements on rational agents’ epistemic states, without treating those agents as mathematically ideal (...) reasoners. I’ll argue that agents can fail to know trivial consequences of what they know, but never determinately. Such cases are epistemic oversights on behalf of the agent in question, and the facts about epistemic oversights are always indeterminate facts. As a result, we are never in a position to assert that such-and-such constitutes an epistemic oversight for agent i (for we may rationally assert only determinate truths). I then develop formal epistemic models according to which epistemic accessibility relations are vague. Given these models, we can show that epistemic oversights always concern indeterminate cases of knowledge. (shrink)

I argue that rationally persuading another to do something for their own good is sometimes (objectionably) paternalistic. Rational persuasion may express, and be guided by, the motive of distrust in the other’s capacity to gather or weigh evidence, and may intrude on the other’s deliberative activities in ways that conflict with respecting their agency and autonomy. I also examine factors that make a difference to whether (and when) the provision of reasons is respectful.

Every kind of ‘ought’ implies some kind of ‘can’ – but there are many kinds of ‘ought’ and even more kinds of ‘can’. In this essay, I shall focus on a particular kind of ‘ought’ – specifically, on what I shall call the “rational ‘ought’”. On every occasion of use, this kind of ‘ought’ is focused on the situation of a particular agent at a particular time; but this kind of ‘ought’ is concerned, not with how that agent acts (...) at that time, but with what beliefs or intentions the agent has at the time, or with the sort of reasoning by means of which the agent at that time forms or revises those beliefs or intentions. (shrink)

People draw subtle distinctions in the normative domain. But it remains unclear exactly what gives rise to such distinctions. On one prominent approach, emotion systems trigger non-utilitarian judgments. The main alternative, inspired by Chomskyan linguistics, suggests that moral distinctions derive from an innate moral grammar. In this article, we draw on Bayesian learning theory to develop a rational learning account. We argue that the ‘size principle’, which is implicated in word learning, can also explain how children would use scant (...) and equivocal evidence to interpret candidate rules as applying more narrowly than utilitarian rules. (shrink)

Left freely to themselves, a group of rational individuals often fail to cooperate even when the product of social cooperation is beneficial to all. Hence, the author argues, a rule of collective decision making is clearly needed that specifies how social cooperation should be organised among contributing individuals. Suzumura gives a systematic presentation of the Arrovian impossibility theorems of social choice theory, so as to describe and enumerate the various factors that are responsible for the stability of the voluntary (...) association of free and rational individuals. Among other topics covered are an axiomatic characterisation of the concept of a rational choice, the simple majority decision rule and its extensions, the social choice implications of the concept of equity as nonenvy, the constrained majoritarian collective choice rules and the conflict between the Paretian ethics and the libertarian claims of individual rights. (shrink)

THE SOCIOLOGICAL TURN The problem we are concerned with is just this: How should we understand science? Are we to account for scientific knowledge (or ...

A general form is proposed for epistemological theories, the relevant factors being: the family of epistemic judgments, the epistemic state, the epistemic commitment , and the family of possible epistemic inputs . First a simple theory is examined in which the states are probability functions, and the subject of probability kinematics introduced by Richard Jeffrey is explored. Then a second theory is examined in which the state has as constituents a body of information and a recipe that determines the accepted (...) epistemic judgments on the basis of this corpus. Through an examination of several approaches to the statistical syllogism, a relation is again established with Jeffrey's generalized conditionalization. (shrink)

Can moral judgements be true or false? Can rational methods be applied to ethics? In this landmark study, Sprigge gives an account of how philosophers have tackled these questions and puts forward his own theory on the matter.

Some irrational states can be avoided in more than one way. For example, if you believe that you ought to A you can avoid akrasia by intending to A or by dropping the belief that you ought to A. This supports the claim that some rational requirements are wide-scope. For instance, the requirement against akrasia is a requirement to intend to A or not believe that you ought to A. But some writers object that this Wide-Scope view ignores asymmetries (...) between the different ways of avoiding irrationality. In this paper I defend the Wide-Scope view against recent objections of this sort from Mark Schroeder and Niko Kolodny. I argue that once we are clear about what the Wide-Scope view is committed to—and, importantly, what it is not—we can see that Schroeder and Kolodny’s objections fail. (shrink)

The “paradox of fictional emotions” involves a trio of claims that are jointly inconsistent but individually plausible. Resolution of the paradox thus requires that we deny at least one of these plausible claims. The paradox has been formulated in various ways, but for the purposes of this chapter, we will focus on the following three claims, which we will refer to respectively as the Response Condition, the Belief Condition and the Coordination Condition.

In this book Joseph Heath brings Jürgen Habermas's theory of communicative action into dialogue with the most sophisticated articulation of the instrumental conception of practical rationality-modern rational choice theory. Heath begins with an overview of Habermas's action theory and his critique of decision and game theory. He then offers an alternative to Habermas's use of speech act theory to explain social order and outlines a multidimensional theory of rational action that includes norm-governed action as a specific type.In the (...) second part of the book Heath discusses the more philosophical dimension of Habermas's conception of practical rationality. He criticizes Habermas's attempt to introduce a universalization principle governing moral discourse, as well as his criteria for distinguishing between moral and ethical problems. Heath offers an alternative account of the level of convergence exhibited by moral argumentation, drawing on game-theoretic models to specify the burden of proof that the theory of communicative action and discourse must assume. (shrink)

How do we know what's (metaphysically) possible and impossible? Arguments from Kripke and Putnam suggest that possibility is not merely a matter of (coherent) conceivability/imaginability. For example, we can coherently imagine that Hesperus and Phosphorus are distinct objects even though they are not possibly distinct. Despite this apparent problem, we suggest, nevertheless, that imagination plays an important role in an adequate modal epistemology. When we discover what is possible or what is impossible, we generally exploit important connections between what is (...) possible and what we can coherently imagine. We can often come to knowledge of metaphysical modality a priori. (shrink)

A notorious problem that has recently received increased attention in axiology, normative theory and population ethics is the apparent ubiquity of what can be generally called nondeterminacy. This paper illustrates how nondeterminacy can spawn cyclical rankings. So, accepting that practical reasons can admit of nondeterminacy challenges the widely held idea that ‘better than’ is transitive. As a result, standard approaches to rational choice under nondeterminacy fail to be action-guiding, since in some situations all options are dominated, that is, impermissible (...) according to standard rational choice criteria. (shrink)