Probability can be used to measure degree of belief in two ways: objectively and subjectively. The objective measure is a measure of the rational degree of belief in a proposition given a set of evidential propositions. The subjective measure is the measure of a particular subject’s dispositions to decide between options. In both measures, certainty is a degree of belief 1. I will show, however, that there can be cases where one belief is stronger than another yet both beliefs are (...) plausibly measurable as objectively and subjectively certain. In ordinary language, we can say that while both beliefs are certain, one belief is more certain than the other. I will then propose second, non probabilistic dimension of measurement, which tracks this variation in certainty in such cases where the probability is 1. A general principle of rationality is that one’s subjective degree of belief should match the rational degree of belief given the evidence available. In this paper I hope to show that it is also a rational principle that the maximum stake size at which one should remain certain should match the rational weight of certainty given the evidence available. Neither objective nor subjective measures of certainty conform to the axioms of probability, but instead are measured in utility. This has the consequence that, although it is often rational to be certain to some degree, there is no such thing as absolute certainty. (shrink)

The value of knowledge can vary in that knowledge of important facts is more valuable than knowledge of trivialities. This variation in the value of knowledge is mirrored by a variation in evidential standards. Matters of greater importance require greater evidential support. But all knowledge, however trivial, needs to be evidentially certain. So on one hand we have a variable evidential standard that depends on the value of the knowledge, and on the other, we have the invariant standard of evidential (...) certainty. This paradox in the concept of knowledge runs deep in the history of philosophy. We approach this paradox by proposing a bet settlement theory of knowledge. Degrees of belief can be measured by the expected value of a bet divided by stake size, with the highest degree of belief being probability 1, or certainty. Evidence sufficient to settle the bet makes the expectation equal to the stake size and therefore has evidential probability 1. This gives us the invariant evidential certainty standard for knowledge. The value of knowledge relative to a bet is given by the stake size. We propose that evidential probability can vary with stake size, so that evidential certainty at low stakes does not entail evidential certainty at high stakes. This solves the paradox by allowing that certainty is necessary for knowledge at any stakes, but that the evidential standards for knowledge vary according to what is at stake. We give a Stake Size Variation Principle that calculates evidential probability from the value of evidence and the stakes. Stake size variant degrees of belief are probabilistically coherent and explain a greater range of preferences than orthodox expected utility theory, namely the Ellsberg and Allais preferences. The resulting theory of knowledge gives an empirically adequate, rationally grounded, unified account of evidence, value and probability. (shrink)

Abstract The Preface Paradox, first introduced by David Makinson (1961), presents a plausible scenario where an agent is evidentially certain of each of a set of propositions without being evidentially certain of the conjunction of the set of propositions. Given reasonable assumptions about the nature of evidential certainty, this appears to be a straightforward contradiction. We solve the paradox by appeal to stake size sensitivity, which is the claim that evidential probability is sensitive to stake size. The argument is that (...) because the informational content in the conjunction is greater than the sum of the informational content of the conjuncts, the stake size in the conjunction is higher than the sum of the stake sizes in the conjuncts. We present a theory of evidential probability that identifies knowledge with value and allows for coherent stake sensitive beliefs. An agent’s beliefs are represented two dimensionally as a bid – ask spread, which gives a bid price and an ask price for bets at each stake size. The bid ask spread gets wider when there is less valuable evidence relative to the stake size, and narrower when there is more valuable evidence according to a simple formula. The bid-ask spread can represent the uncertainty in the first order probabilistic judgement. According to the theory it can be coherent to be evidentially certain at low stakes, but less than certain at high stakes, and therefore there is no contradiction in the Preface. The theory not only solves the paradox, but also gives a good model of decisions under risk that overcomes many of the problems associated with classic expected utility theory. (shrink)

Abstract Argument is seen as central to philosophy, especially epistemology. It is often said that philosophy teaches you to argue for any position. Arguments are used to justify beliefs and many people suppose that for a belief to be counted for knowledge it must be justified. In science, scientific theories must be backed by the evidence and it has been proposed that the relationship of evidence to theory is that of argument to conclusion. But is argument really so important? Arguments (...) in practice are hardly ever persuasive, and a deductive argument adds no new information. Knowledge and wisdom of the philosophical kind can be garnered and created through observation, exploration, experiment, collaboration, narrative and sharing. None of these ways of knowing necessarily involve argument, and can actually in some cases be harmed by argument. It is fairly uncontroversial to say that argument has a central role in contemporary English speaking philosophy. But if argument is a form of combat then this emphasis on argument could be a source of gender bias in philosophy and in certain sciences. Men are physiologically attracted to combat through the mechanism of testosterone fluctuations in response to competitive situations. But apart from being attractive to some men, arguments do not create good philosophy. Good philosophy aims at the love of wisdom and knowledge. Two principle goods in philosophy are the creation of knowledge and the spreading of knowledge. Arguments neither create knowledge nor are persuasive. On the contrary, arguments create divisions and cognitive biases. As such philosophy may be better with less of an emphasis on argument, and more emphasis on non-violence, sharing and love. (shrink)

In this essay I hope to establish that truth is not a necessary condition for knowledge. This is not to go so far as that it is possible to know falsehoods, since not everything that is not true is therefore false. Rather the aim is to show that knowledge is that in which we are fully confident, where our confidence is supported by conclusive evidence. If these two conditions are met, then there is no further condition, truth, that needs to (...) be met in order for us to be in possession of knowledge. (shrink)

Julian Schlöder (2018) examines Timothy Williamson's proposal that knowledge is the norm of assertion within the context of deontic logic. He argues for two claims, one concerning the formalisation of the thesis that knowledge is a norm of assertion and another concerning the formalisation of the thesis that knowledge is the only norm of assertion. On the basis of these claims, Schlöder goes on to raise a series of problems for Williamson's proposal. In response, I argue that both of Schlöder's (...) claims can—and should—be rejected. (shrink)

Factory farming continues to grow around the world as a low-cost way of producing animal products for human consumption. However, many of the practices associated with intensive animal farming have been criticized by public health professionals and animal welfare advocates. The aim of this essay is to raise three independent moral concerns with factory farming, and to explain why the practices associated with factory farming flourish despite the cruelty inflicted on animals and the public health risks imposed on people. I (...) conclude that the costs of factory farming as it is currently practiced far outweigh the benefits, and offer a few suggestions for how to improve the situation for animals and people. (shrink)

It is widely agreed that one of the core functions of government is to supply public goods that markets either fail to provide or cannot provide efficiently. I will suggest that arguments for government provision of public goods require fundamental moral judgments in addition to the usual economic considerations about the relative efficacy of markets and governments in supplying them. While philosophers and policymakers owe a debt of gratitude to economists for developing the theory of public goods, the link between (...) public goods and public policy cannot be forged without moral reflection on the proper function and scope of government power. (shrink)

Abstract:Trust is important for a variety of social relationships. Trust facilitates trade, which increases prosperity and induces us to interact with people of different backgrounds on terms that benefit all parties. Trade promotes trustworthiness, which enables us to form meaningful as well as mutually beneficial relationships. In what follows, I argue that when we erect institutions that enhance trust and reward people who are worthy of trust, we create the conditions for a certain kind of moral progress.

On most accounts, beliefs are supposed to fit the world rather than change it. But believing can have social consequences, since the beliefs we form underwrite our actions and impact our character. Because our beliefs affect how we live our lives and how we treat other people, it is surprising how little attention is usually given to the moral status of believing apart from its epistemic justification. In what follows, I develop a version of the harm principle that applies to (...) beliefs as well as actions. In doing so, I challenge the often exaggerated distinction between forming beliefs and acting on them.1 After developing this view, I consider what it might imply about controversial research the goal of which is to yield true beliefs but the outcome of which might include negative social consequences. In particular, I focus on the implications of research into biological differences between racial groups. (shrink)

See "What's Wrong with Factory Farming?" (2015) for an updated treatment of these issues.

ABSTRACT: This essay examines and criticizes a set of Kantian objections to Parfit's attempt in Reasons and Persons to connect his theory of personal identity to practical rationality and moral philosophy. Several of Parfit's critics have tried to sever the link he forges between his metaphysical and practical conclusions by invoking the Kantian thought that even if we accept his metaphysical theory of personal identity, we still have good practical grounds for rejecting that theory when deliberating about what to do. (...) The argument between Parfit and his opponents illuminates broader questions about the relationship between our metaphysical beliefs and ourpractical reasons.RÉSUMÉ: Cet article examine et critique un ensemble d'objections kantiennes à la tentative de Parfit, dans Reasons and Persons, d'ajuster sa théorie de l'identité personnelle à la rationalité pratique et à la philosophie morale. Plusieurs des critiques de Parfit ont essayé de rompre le lien qu'il tisse entre ses conclusions métaphysiques et pratiques en évoquant l'idée kantienne selon -laquelle, même si nous acceptons sa théorie métaphysique de l'identité personnelle, il existe cependant de bonnes raisons pratiques de rejeter cette théorie lorsque nous délibérons à propos de ce que nous devons faire. Le débat entre Parfit et ses adversaires nous éclaire sur un questionnement plus large à propos du rapport entre croyance métaphysique et raison pratique. (shrink)

A Troublesome Inheritance, by Nicholas Wade, should be read by anyone interested in race and recent human evolution. Wade deserves credit for challenging the popular dog­ma that biological differences between groups either don't exist or cannot ex­plain the relative success of different groups at different tasks. Wade's work should be read alongside another re­cent book, The 10,000 Year Explosion: How Civilization Accelerated Human Evolution, by Gregory Cochran and Henry Harpending. Together, these books represent a ma­jor turning point in the public (...) debate about the speed with which relatively isolated groups can evolve: both books suggest that small genetic differences between members of different groups can have large impacts on their abilities and propensities, which in turn affect the outcomes of the societies in which they live. (shrink)

This discussion revises and extends Jonny Anomaly's ‘public goods’ account of public health ethics in light of recent criticism from Richard Dees. Public goods are goods that are both non-rival and non-excludable. What is significant about such goods is that they are not always provided efficiently by the market. Indeed, the state can sometimes realize efficiency gains either by supplying such goods directly or by compelling private purchase. But public goods are not the only goods that the market may (...) fail to provide efficiently. This point to a way of broadening the public goods account of public health to accommodate Dees' counterexamples, without abandoning its distinctive appeal. On the market failures approach to public health ethics, the role of public health is to correct public health-related market failures of all kinds, so far as possible. The underlying moral commitment is to economic efficiency in the sense of Pareto: if we can re-allocate resources in the economy so as to raise the welfare of some without lowering the welfare of any other, we ought to do so. (shrink)