I argue that you can have a priori knowledge of propositions that neither are nor appear necessarily true. You can know a priori contingent propositions that you recognize as such. This overturns a standard view in contemporary epistemology and the traditional view of the a priori, which restrict a priori knowledge to necessary truths, or at least to truths that appear necessary.

This book defends a radical new theory of contingency as a physical phenomenon. Drawing on the many-worlds approach to quantum theory and cutting-edge metaphysics and philosophy of science, it argues that quantum theories are best understood as telling us about the space of genuine possibilities, rather than as telling us solely about actuality. When quantum physics is taken seriously in the way first proposed by Hugh Everett III, it provides the resources for a new systematic metaphysical framework encompassing possibility, (...) necessity, actuality, chance, counterfactuals, and a host of related modal notions. -/- Rationalist metaphysicians argue that the metaphysics of modality is strictly prior to any scientific investigation; metaphysics establishes which worlds are possible, and physics merely checks which of these worlds is actual. Naturalistic metaphysicians respond that science may discover new possibilities and new impossibilities. This book's quantum theory of contingency takes naturalistic metaphysics one step further, allowing that science may discover what it is to be possible. As electromagnetism revealed the nature of light, as acoustics revealed the nature of sound, as statistical mechanics revealed the nature of heat, so quantum physics reveals the nature of contingency. (shrink)

A brief synopsis of the "contingency" version of the cosmological argument for theism, as developed by Samuel Clarke and explained/examined by William Rowe.

I present and explain a brief version of the "contingency" cosmological argument earlier developed by Samuel Clarke and then updated by William Rowe.

There is a familiar debate between Russell and Strawson concerning bivalence and ‘the present King of France’. According to the Strawsonian view, ‘The present King of France is bald’ is neither true nor false, whereas, on the Russellian view, that proposition is simply false. In this paper, I develop what I take to be a crucial connection between this debate and a different domain where bivalence has been at stake: future contingents. On the familiar ‘Aristotelian’ view, future contingent propositions are (...) neither true nor false. However, I argue that, just as there is a Russellian alternative to the Strawsonian view concerning ‘the present King of France’, according to which the relevant class of propositions all turn out false, so there is a Russellian alternative to the Aristotelian view, according to which future contingents all turn out false, not neither true nor false. The result: contrary to millennia of philosophical tradition, we can be open futurists without denying bivalence. (shrink)

Ian Hacking’s wide-ranging and penetrating analysis of science contains two well-developed lines of thought. The first emphasizes the contingent history of our inquiries into nature, focusing on the various ways in which our concepts and styles of reasoning evolve through time, how their current application is constrained by the conditions under which they arose, and how they might have evolved differently. The second is the mistrust of the idea that the world contains mind-independent natural kinds, preferring nominalism to ‘inherent structurism’. (...) These two pillars of thought seem at first to be mutually reinforcing: the lack of natural structure can help make sense of scientific variability and revision, while variability and revision provide reason to suspect that natural structure is little more than idealization. In what follows, I argue that these two pillars not only fail to support each other, but in fact conflict. One of them must fall, and it is clear which. (shrink)

This book theorises technology and its host of social, material, and epistemic transformation techniques, tools, and methods as indeterminate through sixteen methodologically diverse contributions from media philosophy, art and architectural theory, mathematics, computer science, and anthropology scholars.

In this 1989 book Rorty argues that thinkers such as Nietzsche, Freud, and Wittgenstein have enabled societies to see themselves as historical contingencies, rather than as expressions of underlying, ahistorical human nature or as realizations of suprahistorical goals. This ironic perspective on the human condition is valuable on a private level, although it cannot advance the social or political goals of liberalism. In fact Rorty believes that it is literature not philosophy that can do this, by promoting a genuine sense (...) of human solidarity. A truly liberal culture, acutely aware of its own historical contingency, would fuse the private, individual freedom of the ironic, philosophical perspective with the public project of human solidarity as it is engendered through the insights and sensibilities of great writers. The book has a characteristically wide range of reference from philosophy through social theory to literary criticism. It confirms Rorty's status as a uniquely subtle theorist, whose writing will prove absorbing to academic and nonacademic readers alike. (shrink)

The purpose of this paper is to address Rorty’s critique of Dewey’s notion of experience and to reaffirm a view in which the call to experience is indispensable for a genuinely contingent philosophy. In the first part, I analyze Rorty’s critique of Dewey and show its inconsistency. In the second part, I draw a comparison between their aesthetic views and argue that a true aesthetic experience must consist in the cultivation and creative transfiguration of situational resistances. In the third part, (...) using Jane Addams as an example, I illustrate how at Hull House the resistances provided by the situation were transfigured into original and meaningful aesthetic experiences that touched people’s lives and allowed for a meaningful and intelligent reconstruction. (shrink)

This paper investigates the degree to which information theory, and the derived uses that make it work as a metaphor of our age, can be helpful in thinking about God’s immanence and transcendance. We ask when it is possible to say that a consciousness has to be behind the information we encounter. If God is to be thought about as a communicator of information, we need to ask whether a communication system has to pre-exist to the divine and impose itself (...) to God. If we want God to be Creator, and not someone who would work like a human being, ‘creating’ will mean sustaining in being as much the channel, the material system, as the message. Is information control? It seems that God’s actions are not going to be informational control of everything. To clarify the issue, we attempt to distinguish two kinds of ‘genialities’ in nature, as a way to evaluate the likelihood of God from nature. We investigate concepts and images of God, in terms of the history of ideas but also in terms of philosophical theology, metaphysics, and religious ontology. (shrink)

At least since Aristotle’s famous 'sea-battle' passages in On Interpretation 9, some substantial minority of philosophers has been attracted to the doctrine of the open future--the doctrine that future contingent statements are not true. But, prima facie, such views seem inconsistent with the following intuition: if something has happened, then (looking back) it was the case that it would happen. How can it be that, looking forwards, it isn’t true that there will be a sea battle, while also being true (...) that, looking backwards, it was the case that there would be a sea battle? This tension forms, in large part, what might be called the problem of future contingents. A dominant trend in temporal logic and semantic theorizing about future contingents seeks to validate both intuitions. Theorists in this tradition--including some interpretations of Aristotle, but paradigmatically, Thomason (1970), as well as more recent developments in Belnap, et. al (2001) and MacFarlane (2003, 2014)--have argued that the apparent tension between the intuitions is in fact merely apparent. In short, such theorists seek to maintain both of the following two theses: (i) the open future: Future contingents are not true, and (ii) retro-closure: From the fact that something is true, it follows that it was the case that it would be true. It is well-known that reflection on the problem of future contingents has in many ways been inspired by importantly parallel issues regarding divine foreknowledge and indeterminism. In this paper, we take up this perspective, and ask what accepting both the open future and retro-closure predicts about omniscience. When we theorize about a perfect knower, we are theorizing about what an ideal agent ought to believe. Our contention is that there isn’t an acceptable view of ideally rational belief given the assumptions of the open future and retro-closure, and thus this casts doubt on the conjunction of those assumptions. (shrink)

The contingency of biological regularities—and its implications for the existence of biological laws—has long puzzled biologists and philosophers. The best argument for the contingency of biological regularities is John Beatty’s evolutionary contingency thesis, which will be re-analyzed here. First, I argue that in Beatty’s thesis there are two versions of strong contingency used as arguments against biological laws that have gone unnoticed by his commentators. Second, Beatty’s two different versions of strong contingency are analyzed in (...) terms of two different stabilities of regularities. Third, I argue that Beatty and his commentators have focused on the more ineffective trajectory stability version of the argument, whereas the constancy stability version provides a more substantial and applicable argument against the existence of biological laws. Fourth, I develop a counterexample to Beatty’s thesis. Finally, I discuss the possibility of evolution producing repeatable and general non-lawlike regularities and patterns by utilizing the notion of generative entrenchment and by criticizing the thesis of multiple realizability of biological properties. (shrink)

According to the Principle of Sufficient Reason (‘PSR’), every fact has an explanation for why it obtains. If the PSR is true, there must be a sufficient reason for why God chose to create our world. But a sufficient reason for God’s choice plausibly necessitates that choice. It thus seems that God could not have done otherwise, and that our world exists necessarily. We therefore appear forced to pick between the PSR, and the contingency of creation and divine choice. (...) I show that a third option remains open, and thus that it is possible to preserve the contingency of creation and divine choice even while endorsing the PSR. My solution depends on the coherence of a restricted modal realism. On this modal realism, there is more than one possible morally optimal created world, and for each such world there is an existing possibility in which God creates that world. (shrink)

Offers the first comprehensive survey of Mexican existentialism to appear in English. This book examines the emergence of existentialism in Mexico in the 1940s and the quest for a genuine Mexican philosophy that followed it. It focuses on the pivotal moments and key figures of the Hyperion group, including Emilio Uranga, Luis Villoro, Leopoldo Zea, and Jorge Portilla, who explored questions of interpretation, marginality, identity, and the role of philosophy. Carlos Alberto Sánchez was the first to introduce and emphasize the (...) philosophical significance of the Hyperion group to readers of English in The Suspension of Seriousness, and in the present volume he examines its legacy and relevancy for the twenty-first century. Sánchez argues that there are lessons to be learned from Hyperion’s project not only for Latino/a life in the United States but also for the lives of those on the fringes of contemporary, postmodern or postcolonial, economic, political, and cultural power. (shrink)

Contingent transcranialists claim that the physical mechanisms of mind are not exclusively intracranial and that genuine cognitive systems can extend into cognizers' physical and socio-cultural environments. They further claim that extended cognitive systems must include the deep functional integration of external environmental resources with internal neural resources. They have found it difficult, however, to explicate the precise nature of such deep functional integration and provide compelling examples of it. Contingent intracranialists deny that extracranial resources can be components of genuine extended (...) cognitive systems. They claim that transcranialists fallaciously conflate coupling with constitution and construe cognition as extending always from brains into world rather than world into brains. By using insights from recent research in developmental psychology and by explicating the nature of one form that deep functional integration can take, I argue that (i) transcranialists do not fallaciously conflate coupling wth constitution, and (ii) human emotional ontogenesis is a world-to-brain transcranial achievement. Jennifer Greenwood is a PhD Candidate in Philosophy at the School of History, Philosophy, Religion, and Classics, University of Queensland. (shrink)

It is a philosophical truism that we must think of others as moral agents, not merely as causal or statistical objects. But why? I argue that this follows from the best resolution of an antinomy between our experience of morality as necessarily binding on the will and our knowledge that all moral beliefs originate in contingent histories. We can address this antinomy only by understanding moral deliberation via interpersonal relationships, which simultaneously vindicate and constrains morality’s bind on the will. This (...) means that moral agency is fundamentally social. I model an attitude toward our causal nature on sociologist Erving Goffman’s concept of ‘civil inattention’; our social practice of agency requires that we give minimal attention to the contingent origins of moral judgments in ourselves and others. Understood this way, seeing ourselves as moral agents requires avoiding appeal to causal aetiology to settle substantive moral disagreement. (shrink)

Identities formed with proper names may be contingent. this claim is made first through an example. the paper then develops a theory of the semantics of concrete things, with contingent identity as a consequence. this general theory lets concrete things be made up canonically from fundamental physical entities. it includes theories of proper names, variables, cross-world identity with respect to a sortal, and modal and dispositional properties. the theory, it is argued, is coherent and superior to its rivals, in that (...) it stems naturally from a systematic picture of the physical world. (shrink)

This paper first argues that we can bring out a tension between the following three popular doctrines: (i) the canonical reduction of metaphysical modality to essence, due to Fine, (ii) contingentism, which says that possibly something could have failed to be something, and (iii) the doctrine that metaphysical modality obeys the modal logic S5. After presenting two such arguments (one from the theorems of S4 and another from the theorems of B), I turn to exploring various conclusions we might draw (...) in light of these results, and argue that none comes cost free. In the course of laying out possible responses to my arguments, we'll have a chance to evaluate various doctrines about the interplay between contingency and essence, as well as develop some alternative reductions of metaphysical modality to essence. I don't decisively come down in favor of one response over the others, though I say some things that point towards the conclusion that essence has no role to play in reducing metaphysical modality. (shrink)

In this, the first major philosophical study of contingent pacifism, Larry May offers a new account of pacifism from within the Just War tradition. Written in a non-technical style, the book features real-life examples from contemporary wars and applies a variety of approaches ranging from traditional pacifism and human rights to international law and conscientious objection. May considers a variety of thinkers and theories, including Hugo Grotius, Kant, Socrates, Seneca on restraint, Tertullian on moral purity, Erasmus's arguments against just war, (...) and Hobbes's conception of public conscience. The guiding idea is that the possibility of a just war is conceded, but not at the current time or in the foreseeable future due to the nature of contemporary armed conflict and geopolitics - wars in the past are also unlikely to have been just wars. This volume will interest scholars and upper-level students of political philosophy, philosophy of law, and war studies. (shrink)

There is widespread disagreement as to what the facts are concerning just when a collection of objects composes some further object; but there is widespread agreement that, whatever those facts are, they are necessary. I am unhappy to simply assume this, and in this paper I ask whether there is reason to think that the facts concerning composition hold necessarily. I consider various reasons to think so, but find fault with each of them. I examine the theory of composition as (...) identity, but argue that the version of this doctrine that entails universalism is implausible. I consider the claim that the a priority of such facts leads to their necessity, but give a defence of substantial contingent a priori truths. I ask whether the contingency of such facts would lead to unwelcome possibilities, but argue that the worrying looking possibilities can be blocked if it is desired. Next, I argue against the thought that the Lewis-Sider argument against restricted composition might give us reason to accept the necessity of universalism. Lastly, I respond to two objections from the 2006 BSPC. I conclude in favour of the contingency of the facts concerning when some things compose some thing. (shrink)

The argument is not, however, problem-free. First: while the meaning of s might not guarantee a verifying state of affairs, mightn’t the fact of one’s believing that s is true guarantee a verifying state of affairs? And mightn’t this fact be exploited to secure knowledge of truths that are deeply contingent? Second: the argument seems to rely on the principle that if I can conceive that not P is actually the case, then I do not know that P. But it (...) is generally agreed that a knowledge-conferring warrant for some P need not offer a watertight guarantee of P and thus need not render it inconceivable that the actual world falsifies P. Why then require such a guarantee when it comes to priori warrant? The first objection is that a guarantee of truth need not come from semantics. The second is that no such guarantee is required for a priori knowledge. I shall be exploring both of these ideas in what follows. (shrink)

What is the relationship between evolutionary contingency and diversity? The evolutionary contingency thesis emphasizes dependency relations and chance as the hallmarks of evolution. While contingency can be destructive of, for example, the fragile and complex dynamics in an ecosystem, I will mainly focus on the productive or causal aspect of contingency for a particular sort of diversity. There are many sorts of diversities: Gould is most famous for his diversity-to-decimation model, which includes disparate body plans distinguishing (...) different phyla. However, structural diversity construed more broadly spans scales, such as organization in and among cells, structural arrangements and biomechanics on various scales, and even the profile of ancestor-descendent relationships or community structure of interactions within ecosystems. By focusing on stochastic processes in contingent evolution, I argue that contingency causes structural diversity. Specifically, I focus on the plurality of structural types of cells, genetic codes, and phyla diversity as case studies. (shrink)

Contingencies in Nature may be explained, but such explanations refer to other contingencies (pt. I). Is there a way to “explain away” all contingencies? The first physical theory of modern times, Newton’s theory of gravitation, was received in a way that leaves this question open (pt. II), while Kepler’s theory of cosmological harmony arrived at a positive solution (pt. III). However, later developments in science outdated Kepler’s approach (pt. IV).

I argue against a principle that is widely taken to govern metaphysical explanation. This is the principle that no necessary facts can, on their own, explain a contingent fact. I then show how this result makes available a response to a longstanding objection to the Principle of Sufficient Reason—the objection that the Principle of Sufficient Reason entails that the world could not have been otherwise.

Kripke maintains that one who stipulatively introduces the term ' one meter' as a rigid designator for the length of a certain stick s at time t is in a position to know a priori that if s exists at t then the length of s at t is one meter. Some (e.g., Soames 2003) have objected to this alleged instance of the contingent a priori on the grounds that the stipulator's knowledge would have to be based in part on (...) substantive metalinguistic knowledge. I examine Soames's argument for the a posteriority of the relevant metalinguistic knowledge, and I argue that its main premise is false. (shrink)

In this study John Bowlin argues that Aquinas's moral theology receives much of its character and content from an assumption about our common lot: the good we desire is difficult to know and to will, in particular because of contingencies of various kinds - within ourselves, in the ends and objects we pursue, and in the circumstances of choice. Since contingencies are fortune's effects, Aquinas insists that it is fortune that makes good choice difficult. Bowlin then explicates Aquinas's treatment of (...) a number of topics in light of this difficulty: the moral and theological virtues, the first precepts of the natural law, the voluntariness of virtuous action, and the happiness available to us in this life. By noting that Aquinas proceeds with an eye on fortune's threats to virtue, agency, and happiness, Bowlin places him more precisely in the history of ethics, among Aristotle, Augustine, and the Stoics. (shrink)

Is the cultural evolution of morality fairly contingent? Could cultural evolution have easily led humans to moral norms and judgments that are mostly false by our present lights? If so, does it matter philosophically? Yes, or so we argue. We empirically motivate the contingency of cultural evolution and show that it makes two major philosophical contributions. First, it shows that moral objectivists cannot explain the reliability of our moral judgments and thus strengthens moral debunking arguments. Second, it shows that (...) the reliability of our moral judgments is evidence for theism over metaphysical naturalism. (shrink)

The argument is not, however, problem-free. First: while the meaning of s might not guarantee a verifying state of affairs, mightn’t the fact of one’s believing that s is true guarantee a verifying state of affairs? And mightn’t this fact be exploited to secure knowledge of truths that are deeply contingent? Second: the argument seems to rely on the principle that if I can conceive that not P is actually the case, then I do not know that P. But it (...) is generally agreed that a knowledge-conferring warrant for some P need not offer a watertight guarantee of P and thus need not render it inconceivable that the actual world falsifies P. Why then require such a guarantee when it comes to priori warrant? The first objection is that a guarantee of truth need not come from semantics. The second is that no such guarantee is required for a priori knowledge. I shall be exploring both of these ideas in what follows. (shrink)

Hardly anyone denies that (nearly) all human beings have equal moral status and therefore should be considered and treated as equals. Yet, if humans possess the property that confers moral status upon them to an unequal degree, how come they should be considered and treated as equals? It has been argued that this is because the variations in the degree to which the status‐conferring property is held above a relevant threshold are contingencies that do not generate differences in degrees of (...) moral status. Call this the contingency argument for the basis of moral equality. In this paper, I reject the contingency argument. Instead, I develop an attitude‐based account of the basis of moral equality: according to this account, the basis of moral equality lies in a fitting, basic, and independent moral attitude which is owed to human beings qua moral status‐holders, and provides a coherent and plausible explanation for why the variations above the threshold for moral status do not matter. (shrink)

The argument is not, however, problem-free. First: while the meaning of s might not guarantee a verifying state of affairs, mightn’t the fact of one’s believing that s is true guarantee a verifying state of affairs? And mightn’t this fact be exploited to secure knowledge of truths that are deeply contingent? Second: the argument seems to rely on the principle that if I can conceive that not P is actually the case, then I do not know that P. But it (...) is generally agreed that a knowledge-conferring warrant for some P need not offer a watertight guarantee of P and thus need not render it inconceivable that the actual world falsifies P. Why then require such a guarantee when it comes to priori warrant? The first objection is that a guarantee of truth need not come from semantics. The second is that no such guarantee is required for a priori knowledge. I shall be exploring both of these ideas in what follows. (shrink)

I argue that Kant acknowledges two models of spontaneous self-determination that rational beings are capable of. The first model involves absolute unconditional necessity and excludes any form of contingency. The second model involves (albeit not as a matter of definition) a form of contingency which entails alternative possibilities for determining oneself. The first model would be exhibited by a divine being; the second model is exhibited by human beings. Human beings do, however, partake in the divine model up (...) to an extent, namely, as far as the legislative spontaneity of their law-giving faculties are concerned. I conclude by suggesting that for Kant, the mechanistic principle that we are exclusively determined by natural causes poses a twofold threat for human agency. In one respect (in relation to the second model), it threatens us with the obliteration of contingency, or with the universality of hypothetical necessity. But in another respect (in relation to the first model), it threatens us (and our putative "laws") with the obliteration of absolute necessity, or with the universality of contingency. (shrink)

The philosophical, logical, and terminological junctions between Description Logics (DLs) and Modal Logic (ML) are important because they can support the formal analysis of modal notions of ‘possibility’ and ‘necessity’ through the lens of DLs. This paper introduces functional contingents in order to (i) structurally and terminologically analyse ‘functional possibility’ and ‘functional necessity’ in DL world descriptions and (ii) logically and terminologically annotate DL world descriptions based on functional contingents. The most significant contributions of this research are the logical characterisation (...) and terminological analysis of functional contingents in DL world descriptions. The ultimate goal is to investigate how modal operators can – logically and terminologically – be expressed within DL world descriptions. (shrink)

Grounding contingentism is the doctrine according to which grounds are not guaranteed to necessitate what they ground. In this paper I will argue that the most plausible version of contingentism is incompatible with the idea that the grounding relation is transitive, unless either ‘priority monism’ or ‘contrastivism’ are assumed.

Recently, philosophers have sought to determine the nature of individuals relevant to evolution by natural selection or evolutionary individuals. The Evolutionary Contingency Thesis is a claim about evolution that emphasizes the role of contingency or dependency relations and chance-based factors in how evolution unfolds. In this article, I argue that if we take evolutionary contingency seriously, then we should be pluralists about the types of individuals in selection.

If it is not now determined whether there will be a sea battle tomorrow, can an assertion that there will be one be true? The problem has persisted because there are compelling arguments on both sides. If there are objectively possible futures which would make the prediction true and others which would make it false, symmetry considerations seem to forbid counting it either true or false. Yet if we think about how we would assess the prediction tomorrow, when a sea (...) battle is raging (or not), it seems we must assign the utterance a definite truth-value. I argue that both arguments must be given their due, and that this requires relativizing utterance-truth to a context of assessment. I show how this relativization can be handled in a rigorous formal semantics, and I argue that we can make coherent sense of assertion without assuming that utterances have their truth-values absolutely. (shrink)

Trevor Teitel (2017) has recently argued that combining the assumption that modality reduces to essence with the assumption that possibly some objects contingently exist leads to problems if one wishes to uphold that the logic of metaphysical modality is S5. In this paper I will argue that there is a way for the essentialist to evade the problem described by Teitel. The proposed solution crucially involves the assumption that some propositions possibly fail to exist. I will show how this assumption (...) affords a motivated contingentist response to Teitel’s argument. (shrink)

The just war tradition began life, primarily in the writings of Augustine and other Church Fathers, as a reaction to pacifism. In my view, contemporary just war adherents should also see pacifism as their main rival. The key question of the just war tradition is how to justify war, given that war involves intentionally attacking or killing innocent people. And this justificatory enterprise is not an easy one. Today some theorists argue that some, but not all, soldiers are liable to (...) be attacked, especially those who fight in an unjust war. In this view, some of those who fight and kill in unjust wars should not be excused for following orders or even for their ignorance. Yet, it is often hard to tell if one is fighting in an unjust war, or whether military orders are unjust. I will argue that, especially in light of new work by just war adherents, the moral risks of participating in war are so high that pacifism, at least in its contingent form, should be seen as a reasonable option. The new versions of the just war doctrine bring us much closer to pacifism than their adherents would admit. (shrink)

Avicenna’s discussion of future contingent propositions is sometimes considered to entail metaphysical indeterminism. In this paper, I argue that his logical analysis of future contingent statements is best understood in terms of the epistemic modality of those statements, which has no consequences for modal metaphysics. This interpretation is corroborated by hitherto neglected material concerning the question of God’s knowledge of particulars. In the Taʿlīqāt, Avicenna argues that God knows particulars by knowing their complete causes, and when contrasted with the human (...) knowledge of particulars, this epistemically superior access shows that the contingency of statements about future particulars is not due to the modal properties of real particulars but to the nature of human access to them. (shrink)

In the first part of the paper it is proved that there exists a one–one mapping between a minimal contingential logic extended with a suitable axiom for a propositional constant τ, named KΔτw, and a logic of necessity ${K\square \tau{w}}$ whose language contains ${\square}$ and τ. The form of the proposed translation aims at giving a solution to a problem which was left open in a preceding paper. It is then shown that the presence of τ in the language of (...) KΔτw allows for the definition, in terms of the non-contingency operator Δ, not only of ${\square}$ but of a second necessity operator O. It is observed that this fact opens the road to an investigation of the τ-free multimodal fragments of KΔτw. (shrink)

Upon discovering that certain beliefs we hold are contingent on arbitrary features of our background, we often feel uneasy. I defend the proposal that if such cases of contingency anxiety involve defeaters, this is because of the epistemic significance of disagreement. I note two hurdles to our accepting this Disagreement Hypothesis. Firstly, some cases of contingency anxiety apparently involve no disagreement. Secondly, the proposal may seem to make our awareness of the influence of arbitrary background factors irrelevant in (...) determining whether to revise our beliefs. I show that each of these problems can be successfully accommodated by the Disagreement Hypothesis. (shrink)