This overview of the philosophy of certainty will distinguish two types of certainty, specify controversial theses about certainty from recent literature, and explain some of the arguments for and against those theses.

When is it permissible to rely on a proposition in practical reasoning? Standard answers to this question face serious challenges. This paper uses these challenges to motivate a certainty norm of practical reasoning. This norm holds that one is permitted to rely on p in practical reasoning if and only if p is epistemically certain. After developing and defending this norm, I consider its broader implications. Taking a certainty norm seriously calls into question traditional assumptions about the importance (...) of belief and knowledge. In particular, it raises the possibility that many epistemological jobs that are usually assigned to belief and knowledge should be reallocated to two related but importantly different states: psychological and epistemic certainty. (shrink)

For Kant, knowledge involves certainty. If “certainty” requires that the grounds for a given propositional attitude guarantee its truth, then this is an infallibilist view of epistemic justification. Such a view says you can’t have epistemic justification for an attitude unless the attitude is also true. Here I want to defend an alternative fallibilist interpretation. Even if a subject has grounds that would be sufficient for knowledge if the proposition were true, the proposition might not be true. And (...) so there is sometimes still rational room for doubt. The goal of this paper is to present four different models of what “certainty” amounts to, for Kant, each of which is compatible with fallibilism. (shrink)

In the philosophical literature on the definition of lying, the analysis is generally restricted to cases of flat-out belief. This chapter considers the complex phenomenon of lies involving partial beliefs – beliefs ranging from mere uncertainty to absolute certainty. The first section analyses lies uttered while holding a graded belief in the falsity of the assertion, and presents a revised insincerity condition, requiring that the liar believes the assertion to be more likely to be false than true. The second (...) section analyses assertions that express graded beliefs, exploring how mitigation and reinforcement can alter the insincerity conditions for lying. The last section considers the case of lies that attack certainty (knowledge-lies), understood as attempt to alter the hearer's graded beliefs. (shrink)

This paper investigates the historical origin and ancestors of typicality, which is now a central concept in Boltzmannian Statistical Mechanics and Bohmian Mechanics. Although Ludwig Boltzmann did not use the word typicality, its main idea, namely, that something happens almost always or is valid for almost all cases, plays a crucial role for his explanation of how thermodynamic systems approach equilibrium. At the beginning of the 20th century, the focus on almost always or almost everywhere was fruitful for developing measure (...) theory and probability theory. It was apparently Hugh Everett III who first mentioned typicality in physics in 1957 while searching for a justification of the Born rule in his interpretation of quantum mechanics. The historically closest concept before these developments is moral certainty, which was invented by the medieval French theologian Jean Gerson, and it became a standard concept at least until the Age of Enlightenment, when Jakob Bernoulli proved the Law of Large numbers. (shrink)

_ Source: _Volume 6, Issue 2-3, pp 120 - 142 This paper aims to contribute to the debate over epistemic versus non-epistemic readings of the ‘hinges’ in Wittgenstein’s _On Certainty_. I follow Marie McGinn’s and Daniele Moyal-Sharrock’s lead in developing an analogy between mathematical sentences and certainties, and using the former as a model for the latter. However, I disagree with McGinn’s and Moyal-Sharrock’s interpretations concerning Wittgenstein’s views of both relata. I argue that mathematical sentences as well as certainties are (...) true and are propositions; that some of them can be epistemically justified; that in some senses they are not prior to empirical knowledge; that they are not ineffable; and that their primary function is epistemic as much as it is semantic. (shrink)

Researchers have debated whether knowledge or certainty is a better candidate for the norm of assertion. Should you make an assertion only if you know it's true? Or should you make an assertion only if you're certain it's true? If either knowledge or certainty is a better candidate, then this will likely have detectable behavioral consequences. I report an experiment that tests for relevant behavioral consequences. The results support the view that assertability is more closely linked to knowledge (...) than to certainty. In multiple scenarios, people were much more willing to allow assertability and certainty to come apart than to allow assertability and knowledge to come apart. (shrink)

Delusions are unhinged hinge certainties. Delusions are defined as strongly anchored beliefs that do not change in the face of adverse evidence. The same goes for Wittgensteinian certainties. My paper refines the so-called framework views of delusion, presenting an argument that epistemically speaking, considering them to be certainties best accounts for delusions’ doxastic profile. Until now there has been little argument in favour of this position and the original proposals made too extreme predictions about the belief systems of delusional patients. (...) I show that my account fares better with the diverse objections that have been raised against older framework views of delusion (Campbell 2001, Gipps and Rhodes 2008). Finally, I examine what makes a harmless hinge into a pathological delusion. (shrink)

This paper seeks to widen the dialogue between the “epistemology of peer disagreement” and the epistemology informed by Wittgenstein’s last notebooks, later edited as On Certainty. The paper defends the following theses: not all certainties are groundless; many of them are beliefs; and they do not have a common essence. An epistemic peer need not share all of my certainties. Which response to a disagreement over a certainty is called for, depends on the type of certainty in (...) question. Sometimes a form of relativism is the right response. Reasonable, mutually recognized peer disagreement over a certainty is possible.—The paper thus addresses both interpretative and systematic issues. It uses Wittgenstein as a resource for thinking about peer disagreement over certainties. (shrink)

During the 1630s Descartes recognized that he could not expect all legitimate claims in natural science to meet the standard of absolute certainty. The realization resulted from a change in his physics, which itself arose not through methodological reflections, but through developments in his substantive metaphysical doctrines. Descartes discovered the metaphysical foundations of his physics in 1629-30; as a consequence, the style of explanation employed in his physical writings changed. His early methodological conceptions, as preserved in the Rules and (...) sketched in Part Two of the Discourse, pertained primarily to his early work in optics. By the early 1630s, Descartes was concerned with new methodological problems pertaining to the postulation of micro-mechanisms. Recognition of the need to employ a method of hypothesis led him to lower the standard of certainty required of particular explanations in his mature physics. (shrink)

We ordinarily assume that we have reliable knowledge of our immediate surroundings, so much so that almost all the time we entrust our lives to the truth of what we take ourselves to know, without a moment’s thought. But if, as Karl Popper and others have maintained, all our knowledge is conjectural, then this habitual assumption that our common sense knowledge of our environment is secure and trustworthy would seem to be an illusion. Popper’s philosophy of science, in particular, fails (...) to do justice to the distinction we ordinarily draw between secure knowledge and mere conjecture. But Popper’s philosophy of science, in particular his attempted solution to the problem of induction, is defective. It fails to take into account that physics, in only accepting unified theories, even though endlessly empirically more successful disunified rivals are always available, makes the persistent metaphysical assumption that all disunified theories are false. Once this point is acknowledged, it becomes clear that a new conception of scientific method is required which sees science as making a hierarchy of metaphysical assumptions concerning the comprehensibility and knowability of the universe. This provides a framework of relatively unproblematic assumptions and associated methods of science within which much more problematic assumptions and associated methods can be critically assessed and improved. This hierarchical view seems at first to intensify the problem of distinguishing certainty from conjecture, in that it emphasizes that scientific knowledge, and even humble common sense knowledge, contain usually unacknowledged cosmological conjectures. But actually it explicates the basis we have for drawing the distinction between trustworthy knowledge and mere conjecture, and even goes some way towards providing a rationale for this distinction, in so far as one exists. (shrink)

Most philosophers, including all materialists I know of, believe that I am a complex thing?a thing with parts?and that my mental life is (or is a result of) the interaction of these parts. These philosophers often believe that I am a body or a brain, and my mental life is (or is a product of) brain activity. In this paper, I develop and defend a novel argument against this view. The argument turns on certainty, that highest epistemic status that (...) a precious few of our beliefs enjoy. For example, on the basis of introspection, I am certain that I am not in fierce pain right now. But if I am a complex thing like a body or a brain, then introspection might be a causal series of events extended in time. And any such process could go awry. So, if introspection is such a process, then I could gain good evidence that the introspective process has gone awry and that I am, contrary to appearances, feeling fierce pain right now. Therefore, the view that I am a complex thing like a body or a brain forces open the possibility that I cannot be certain that I am not feeling fierce pain right now. Since that is clearly not an open possibility, it follows that I am not a complex thing. I conclude by responding to three objections. (shrink)

Some people insist that they are dead. Rather than starting with the usual assumption that delusions are ‘false beliefs about external reality’ I want to consider how interpreting their claim as a report of a certain kind of anomalous experience assists us in understanding why they are certain, why their claim is immune from evidence to the contrary, and why they do not act in ways we would expect were they to believe their claim to be true of the world. (...) While this helps us understand cases where people do not act on their delusions, more must be said about the people who do act on their delusions. I shall attempt to describe a process where an intense anomalous experience leads to a context-specific narrowing of attention. The ultimate result of this is that the appearance / reality distinction becomes lost in the context of the anomalous experience. The sense of conviction that would be appropriately associated with a report of experience thus becomes inappropriately associated with a claim about external reality. While there have been efforts to provide cognitive therapy for delusional subjects such therapy seems to be based on the notion that confronting them with their contradictions will assist in weakening their sense of certainty about the delusional utterance. I consider whether more progress could be made via empathetic validation of the sense of certainty which is appropriate when associated with the person’s anomalous experience. (shrink)

It is widely held that assertions are partially governed by an epistemic norm. But what is the epistemic condition set out in the norm? Is it knowledge, truth, belief, or something else? In this paper, I defend a view similar to that of Stanley (2008), according to which the relevant epistemic condition is epistemic certainty, where epistemic certainty (but not knowledge) is context-sensitive. I start by distinguishing epistemic certainty, subjective certainty, and knowledge. Then, I explain why (...) it's much more plausible to think that "certain", rather than "know", is context-sensitive. After that, I respond to an important worry raised by Pritchard, according to which the proposed view is too strong to accommodate our current practice of assertion. I then show that the main linguistic and conversational data advanced in the recent literature in favour of the knowledge condition are best explained by the certainty view. Finally, I offer two principled considerations: the certainty view is the only one compatible with three independently plausible claims and it fits very well with the common thought that knowledge does not entail certainty. (shrink)

This paper argues that we should assign certainty a central place in epistemology. While epistemic certainty played an important role in the history of epistemology, recent epistemology has tended to dismiss certainty as an unattainable ideal, focusing its attention on knowledge instead. I argue that this is a mistake. Attending to certainty attributions in the wild suggests that much of our everyday knowledge qualifies, in appropriate contexts, as certain. After developing a semantics for certainty ascriptions, (...) I put certainty to explanatory work. Specifically, I argue that by taking certainty as our central epistemic notion, we can shed light on a variety of important topics, including evidence and evidential probability, epistemic modals, and the normative constraints on credence and assertion. (shrink)

Newton began his Principia with three Axiomata sive Leges Motus. We offer an interpretation of Newton’s dual label and investigate two tensions inherent in his account of laws. The first arises from the juxtaposition of Newton’s confidence in the certainty of his laws and his commitment to their variability and contingency. The second arises because Newton ascribes fundamental status both to the laws and to the bodies and forces they govern. We argue the first is resolvable, but the second (...) is not. However, the second tension shows that Newton conceives laws as formal causes of bodies and forces. This neo-Aristotelian conception goes missing in Kantian accounts of laws, as well as accounts that stress laws’ grounding in powers and capacities. (shrink)

Hume appeals to different kinds of certainties and necessities in the Treatise. He contrasts the certainty that arises from intuition and demonstrative reasoning with the certainty that arises from causal reasoning. He denies that the causal maxim is absolutely or metaphysically necessary, but he nonetheless takes the causal maxim and ‘proofs’ to be necessary. The focus of this paper is the certainty and necessity involved in Hume’s concept of knowledge. I defend the view that intuitive certainty, (...) in particular, is certainty of the invariability or necessity of relations between ideas. Against David Owen and Helen Beebee, I argue that the certainty involved in intuition depends on the activity of the mind. I argue, further, that understanding this activity helps us understand more clearly one of Hume’s most important theses, namely that experience is the source of a distinct kind of certainty and of necessity. (shrink)

This paper presents a new approach to resolving an apparent tension in Descartes’ discussion of scientific theories and explanations in the Principles of Philosophy. On the one hand, Descartes repeatedly claims that any theories presented in science must be certain and indubitable. On the other hand, Descartes himself presents an astonishing number of speculative explanations of various scientific phenomena. In response to this tension, commentators have suggested that Descartes changed his mind about scientific theories having to be certain and indubitable, (...) that he lacked the conceptual resources to describe the appropriate epistemic attitude towards speculative theories, or that the presence of geometrical principles in these explanations guarantee their certainty. I argue that none of these responses is satisfactory and suggest a different resolution to the tension by examining Descartes’ notion of explanation. On Descartes’ view, providing an adequate explanation does not require being certain of the theories that constitute the explanans. Relatedly, the purpose of Cartesian explanations is not to discover the truth about the various underlying mechanisms that such explanations appeal to, but to support his general philosophical thesis that all natural phenomena can be explained by appealing to the extension of matter. (shrink)

Having a body is one of those unquestionable certainties of which we could not really understand the negation: the latter would not be a legitimate doubt in our linguistic, and therefore the epistemic game. In facts, according to Wittgenstein, contravening certain cornerstones of our language game implies that the used combination of words is being excluded from the game, withdrawn from circulation. The idea of this paper is that the external labelling of a behaviour as a mental illness, prima facie, (...) comes from here. Seriously questioning whether someone else controls my actions or my thoughts or whether I am actually dead, then, are not just doubts, as Wittgenstein's critique of G.E. Moore shows: such believes are constitutively excluded from our way of seeing the world and characterized as illnesses, anomalies; otherwise, it would the complete destruction of the language game we inhabit and therefore of the world as we know it, because we would not know on which bases something could be said truthfully or falsely if we did not even know that "this one is my hand". Therefore, even if mental illnesses objectify themselves in correlative physiological dysfunctions, such a discovery comes only after the external recognition of some symptoms, and to recognize the external symptoms of an illness we have to treat them as such; hereby is suggested that we do treat something this way when it threatens the certainties around which the language game we play revolves. (shrink)

The ways in which Wittgenstein was directly influenced by William James (by his early psychological work as well his later philosophy) have been thoroughly explored and charted by Russell B. Goodman. In particular, Goodman has drawn attention to the pragmatist resonances of the Wittgensteinian notion of hinge propositions as developedand articulated in the posthumously edited and published work, On Certainty. This paper attempts to extend Goodman’s observation, moving beyond his focus on James (specifically, James’s Pragmatism) as his pragmatist reference (...) point. It aims to articulate the affinity between Wittgenstein’s thought on the topic of certainty and that of the neglected pragmatist thinker, George Santayana. -/- The paper draws on Duncan Pritchard’s recent reading of Wittgenstein’s On Certainty in order to articulate the concept of certainty involved in the notion of hinge propositions. It identifies two important and related points of affinity between this Wittgensteinian line of thought on certainty and the line of thought on the same topic articulated in Santayana’s Scepticism and Animal Faith. The paper argues, firstly, that, both lines of thought reflect a pragmatist concept of certainty, according to which our most fundamental certainties are not conceived as purely theoretical objects of belief or knowledge but rather as thearational presuppositions of beliefs and practical action. Secondly, it examines the way inwhich the pragmatist concept of certainty functions, for the two thinkers as a response to scepticism. It argues that although the two thinkers’ responses are very different, they are mutually compatible and, together, point towards the possibility of a distinctively pragmatist response to scepticism, which involves an anti-epistemological model of the intimate relation of the human self to the world. (shrink)

Why do we tend to think that phenomenal consciousness poses a hard problem? The answer seems to lie in part in the fact that we have the impression that phenomenal experiences are presented to us in a particularly immediate and revelatory way: we have a sense of acquaintance with our experiences. Recent views have offered resources to explain such persisting impression, by hypothesizing that the very design of our cognitive systems inevitably leads us to hold beliefs about our own experiences (...) with certainty. I argue against this kind of “designed certainty” views. First, I claim that it is doubtful that we really hold beliefs about our own experiences with certainty—in any sense of certainty that would make our phenomenal beliefs special. Second, I claim that, even if it were the case that we hold beliefs about experiences with certainty, this would fall short of explaining our sense of acquaintance. (shrink)

Many of the most important questions about primitive certainty have to do with the distinction between primitive certainty as a practical attitude or disposition and primitive certainty as a psychological attitude and with the distinction between these and primitive, objective certainty.

In the Principles of Philosophy, Descartes explains several observable phenomena showing that they are caused by special arrangements of unobservable microparticles. Despite these microparticles being unobservable, many passages suggest that he was very confident that these explanations were correct. In other passages, however, Descartes points out that these explanations merely hold the status of “suppositions” or “conjectures” that could be wrong. My main goal in this chapter is to clarify this apparent conflict. I argue first that for Descartes it was (...) indeed possible to have knowledge of unobservable particles and structures, and that the possibility of natural explanations being wrong should be understood as these explanations not being absolutely certain, but only morally certain. I use the debate in contemporary philosophy of science between scientific realism and antirealism as a framework to understand how Cartesian explanations work. Especifically, I argue that Cartesian explanations rely on what Ernan McMullin calls retroduction, which is a mode of inference that justifies beliefs in concrete unobservable entities and processes, based on considerations such as simplicity, coherence, etc. This kind of justification is of common use among scientific realists. Thus, another goal of this chapter is to highlight the relevance of Descartes’ ideas about explanation in the contemporary debate on scientific realism. (shrink)

A common sense view is illustrated by Doubting Thomas, and surfaces in many philosophical and psychological writings : Touching is better than seeing. But can we make sense of this privilege? We rule out that it could mean that touch is more informative than vision, more ‘objective’ or more directly in contact with reality. Instead, we propose that touch offers not a perceptual, but a metacognitive advantage: touch is not more objective than vision but rather provides comparatively higher subjective (...) class='Hi'>certainty. (shrink)

When information on a coma patient’s expected outcome is uncertain, a moral dilemma arises in clinical practice: if life-sustaining treatment is continued, the patient may survive with unacceptably poor neurological prospects, but if withdrawn a patient who could have recovered may die. Continuous electroencephalogram-monitoring is expected to substantially improve neuroprognostication for patients in coma after cardiac arrest. This raises expectations that decisions whether or not to withdraw will become easier. This paper investigates that expectation, exploring cEEG’s impacts when it becomes (...) part of a socio-technical network in an Intensive Care Unit. Based on observations in two ICUs in the Netherlands and one in the USA that had cEEG implemented for research, we interviewed 25 family members, healthcare professionals, and surviving patients. The analysis focuses on the way patient outcomes are constructed, the kind of decision support these outcomes provide, and how cEEG affects communication between professionals and relatives. We argue that cEEG can take away or decrease the intensity of the dilemma in some cases, while increasing uncertainty for others. It also raises new concerns. Since its actual impacts furthermore hinge on how cEEG is designed and implemented, we end with recommendations for ensuring responsible development and implementation. (shrink)

In recent discussions in this journal, Moti Mizrahi defends the claim that knowledge equals epistemic certainty. Howard Sankey finds Mizrahi’s argument to be problematic, since, as he reads it, this would entail that justification must guarantee truth. In this article, I suggest that an account of the normativity of justification is able to bridge the gap between Mizrahi’s proposal and Sankey’s objections.

This book explores a question central to philosophy--namely, what does it take for a belief to be justified or rational? According to a widespread view, whether one has justification for believing a proposition is determined by how probable that proposition is, given one's evidence. In this book this view is rejected and replaced with another: in order for one to have justification for believing a proposition, one's evidence must normically support it--roughly, one's evidence must make the falsity of that proposition (...) abnormal in the sense of calling for special, independent explanation. This conception of justification bears upon a range of topics in epistemology and beyond. Ultimately, this way of looking at justification guides us to a new, unfamiliar picture of how we should respond to our evidence and manage our own fallibility. This picture is developed here. (shrink)

In the 16th century, western science made a great leap. Meanwhile, in China, the development of textual criticism (including scholars Gu Yanwu 1613-1682, Dai Zhen 1724-1777, Duan Yucai 1735-1815, Wang Niansun 1744-1832) also facilitated the development of scientific factors (Hu Shi 1967).This paper argues that Qian-Jia scholars爷work represented a new era of traditional research that the value of scholarships and intellectual work (starting from Gu Yanwu 1613-1682, Dai Zhen 1724-1777, Duan Yucai 1735-1815, Wang Niansun 1744-1832, etc.) is essentially based on (...) what they created and believed, overtly or overtly, the principle of logic certainty—a newly developed indigenous rationalism in the Chinese intellectual history. (shrink)

Coping with everyday life limits the extent of one’s scepticism. It is practically impossible to doubt the existence of the things with which one is immediately engaged and interacting. To doubt that, say, a door exists, is to step back from merely using the door (opening it) and to reflect on it in a detached, theoretical way. It is impossible to simultaneously act and live immersed in situation S while doubting that one is in S. Sceptical doubts—such as ‘Is this (...) really a door?’, ‘Am I really walking?’ — require a reflective withdrawal in thought from the situation at hand. Maintaining sceptical doubt while coping with everyday life requires a split consciousness, a bad faith, with one part of consciousness doubting the existing of things that the other part takes forgranted. For this reason, a sustained lived sceptical doubt is sometimes thought to be impossible. -/- In this article, I examine Wittgenstein's response to scepticism in "On Certainty". I argue that one of his responses is "the response based on action", which is (as other Wittgenstein interpreters have noted) a characteristically pragmatist response. I then evaluate the quality of this pragmatist response to scepticism, noting that actions just as much as representations are susceptible to mis-interpretation. It is argued that despite the insights contained in it, Wittgenstein's contextualism about meaning is inadequate to rescue the Wittgensteinian response to scepticism. (shrink)

While Cavell is well known for his reinterpretation of the later Wittgenstein, he has never really engaged himself with post-Investigations writings like On Certainty. This collection may, however, seem to undermine the profoundly anti-dogmatic reading of Wittgenstein that Cavell has developed. In addition to apparently arguing against what Cavell calls ‘the truth of skepticism’ – a phrase contested by other Wittgensteinians – On Certainty may seem to justify the rejection of whoever dares to question one’s basic presuppositions. According (...) to On Certainty, or so it seems, the only right response to someone with different certainties is a reproach like ‘Fool!’ or ‘Heretic!’. This article aims to show that On Certainty need not be taken to prove Cavell wrong. It explains that Wittgenstein, in line with the first two parts of The Claim of Reason, does not reject scepticism out of hand but rather questions the sceptic’s self-understanding. Using arguments from Part Three of The Claim, the article moreover argues that a confrontation with divergence calls for self-examination rather than self-righteousness. Precisely because Wittgenstein acknowledges ‘the groundlessness of our believing’ or, in Cavellian terms, ‘the truth of skepticism’, he is not the authoritarian thinker that some have taken him to be. (shrink)

This is a reply to Howard Sankey’s comment (“Factivity or Grounds? Comment on Mizrahi”) on my paper, “You Can’t Handle the Truth: Knowledge = Epistemic Certainty,” in which I present an argument from the factivity of knowledge for the conclusion that knowledge is epistemic certainty. While Sankey is right that factivity does not entail epistemic certainty, the factivity of knowledge does entail that knowledge is epistemic certainty.

This dissertation explores how antiquity and some of its early modern admirers understand the notion of certainty, especially as it is theorized in Quintilian's Institutio Oratoria, a first-century educational manual for the aspiring orator that defines certainty in terms of consensus. As part of a larger discussion of argumentative strategies, Quintilian turns to the “nature of all arguments,” which he defines as “reasoning which lends credence to what is doubtful by means of what is certain” (ratio per ea (...) quae certa sunt fidem dubiis adferens: quae natura est omnium argumentorum, V.10.8). These certainties, he later specifies, include not matters of scientific demonstration or objective fact, but the agreements of various communities: the laws of cities, local customs, and other forms of consensus. As the foundation of persuasive rhetoric, these consensus-based certainties situate argumentation as the practice of crafting agreements rather than demonstrating necessary conclusions. Taking as its point of departure Quintilian's novel understanding of certainty, this study looks to some of Quintilian's intellectual forebears as well as his later readers to show how his work is both a nexus of earlier intellectual developments as well as an important inspiration for later accounts of certainty, even into the early modern period. After illustrating in the first chapters of this dissertation how Quintilian's manual incorporates elements from Aristotelian notions of dialectic and rhetoric as well as from Ciceronian skeptical approaches to epistemology, I show how Quintilian's curriculum for the orator shapes the thought of Italian humanists, especially that of Lorenzo Valla (1406–1457), a reformer of scholastic logic and dialectic, and Giambattista Vico (1668–1744), an influential Neapolitan jurist. Adopting Quintilian's rendering of certainty as a matter of agreements and conventions, these later authors elaborate their own novel approaches to various fields—including law, language, and logic—through this ancient understanding of certum. Contrary to modern notions of certainty as objective or scientific fact, Quintilian's humanist readers continue to root this concept in consensus, both within the courtroom and without. (shrink)

In the Bayesian approach to quantum mechanics, probabilities—and thus quantum states—represent an agent’s degrees of belief, rather than corresponding to objective properties of physical systems. In this paper we investigate the concept of certainty in quantum mechanics. Particularly, we show how the probability-1 predictions derived from pure quantum states highlight a fundamental difference between our Bayesian approach, on the one hand, and Copenhagen and similar interpretations on the other. We first review the main arguments for the general claim that (...) probabilities always represent degrees of belief. We then argue that a quantum state prepared by some physical device always depends on an agent’s prior beliefs, implying that the probability-1 predictions derived from that state also depend on the agent’s prior beliefs. Quantum certainty is therefore always some agent’s certainty. Conversely, if facts about an experimental setup could imply agent-independent certainty for a measurement outcome, as in many Copenhagen-like interpretations, that outcome would effectively correspond to a preexisting system property. The idea that measurement outcomes occurring with certainty correspond to preexisting system properties is, however, in conflict with locality. We emphasize this by giving a version of an argument of Stairs [(1983). Quantum logic, realism, and value-definiteness. Philosophy of Science, 50, 578], which applies the Kochen–Specker theorem to an entangled bipartite system. (shrink)

There are at least three interpretations that attempt to read from the Sense-Certainty Chapter a Hegelian theory of indexicals. First, the Impossibility of Singular Reference Reading understands Hegel as excluding in principle the possibility of any linguistic cognition of individuals. Second, the Theory of Reference Reading criticizes the first reading and interprets from Hegel the classical idea of direct reference theory. Third, Brandom’s Anaphoric Theory Reading suggests an alternative explanation while still defending the possibility of knowledge of individuals in (...) Hegel. I criticize the first two readings and argue that the third is the most exegetically and philosophically adequate interpretation. The first interpretation attempts to ascribe to Hegel a sort of skepticism, but this can be at most in a very restricted sense successful and the skepticism constructed in such a way is too trivial to refute Hegel’s position. The second reading is more adequate in that it does not fall into the error that the first one committed, but is still flawed because it introduces a subject-object or mind-world dualism that Hegel denies. The third reading has great advantages compared to the first two readings in terms that it provides a suitable account of indexical knowledge on individuals while avoiding skepticism and dualism which arise in the former readings. (shrink)

In Leibniz’s New Essays stands out, within many important topics, his doctrine of innate ideas, which supposes the division between sense knowledge and innate knowledge and implies the distinction between truths of reason and truths of fact. That doctrine is particularly relevant for Leibniz’s philosophy, but implicitly entails the epistemological difference between belief, on one hand, and certainty, on the other. In this paper I outline, according to my interpretation, how Leibniz explains that humans can have certainty about (...) innate ideas. This topic is important because if Leibniz demonstrates the possibility of having certainty of those ideas, then, it is feasible to believe in its existence. However, if his explanation is unsatisfactory his metaphysical doctrine would be seriously weakened and, at the same time, both skepticism and Locke’s empiricist doctrine would be reinforced. (shrink)

This paper is a companion piece to my earlier paper “Fallibilism and Concessive Knowledge Attributions”. There are two intuitive charges against fallibilism. One is that it countenances the truth (and presumably acceptability) of utterances of sentences such as “I know that Bush is a Republican, though it might be that he is not a Republican”. The second is that it countenances the truth (and presumably acceptability) of utterances of sentences such as “I know that Bush is a Republican, even though (...) I’m not certain that he is”, or “I know that Bush it a Republican, even though it isn’t certain that he is.” In “Fallibilism and Concessive Knowledge Attributions”, I argue that fallibilism in epistemology does not countenance the truth of utterances of sentences such as “I know that Bush is a Republican, though it might be that he is not a Republican”. In this paper, I argue that there are independent reasons for thinking that utterances of sentences such as “I know that Bush is a Republican, though I’m not certain that he is” and “I know that Bush is a Republican, though it’s not certain that he is” are unassertible. More specifically, I argue that these are simply instances of Moore’s Paradox, such as “Dogs bark, but I don’t know that they do.” The right account of Moore’s Paradox does not involve the falsehood of the semantic content of the relevant utterances, but rather their pragmatic unacceptability. So the anti-fallibilist intuitions turn out to have pragmatic, rather than semantic import, and therefore do not tell against the truth of fallibilism. Fallibilism in epistemology is often thought to be theoretically desirable, but intuitively problematic. My purpose with these two papers is to show that fallibilism is not intuitively problematic. (shrink)

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)

I can be wrong about things I seem to perceive; the conditions might lead me to be mistaken about them. Since I can't rule out the possibility that the conditions are misleading, I can't be sure that I am perceiving this thing in my hand correctly. But suppose that I am able to examine it actively—handling it, looking closer, shining a light on it, and so on. Then, my level of uncertainty goes down; in the limit it is eliminated entirely. (...) Of course, I might be mistaken because I am a brain in a vat, or because some other sceptical scenario obtains. But sceptical scenarios apply not just to this thing in my hand, but to everything all at once. Define "empirical certainty" as the absence of the kind of doubt that spreads to all empirical states of affairs. Sensory exploration, or active examination, can in principle lead to empirical certainty. (shrink)

I argue that being wide awake is an epistemic virtue which enables me to recognize immediately that I'm wide awake. Also I argue that dreams are imaginings and that the wide awake mind can immediately discern the difference between imaginings and vivid sense experience. Descartes need only pinch himself.

This thesis develops an account of ethics called the Linguistic Perspective, which is realist in a practical, non-theoretical sense, and is rooted Wittgenstein’s 'On Certainty'. On this account, normativity is intrinsic to human action and language; the norms of ethics are the logical limits of the most basic, unassailable concepts that practical reasoning requires for intelligibility. Part I lays the groundwork for this account by developing a Tractarian Reading of 'On Certainty'. Here, I contend that 'On Certainty' (...) is primarily concerned with the logical requirements and limits of language, and like the 'Tractatus' it develops these concerns in a realist direction. 'On Certainty', I argue, does so by advancing three key claims about logic: Everything descriptive of a language-game is part of logic; the boundary between logical and empirical propositions is not sharp; logic is founded on action. I investigate these claims, with particular emphasis on how natural human reactions provide logical conditions for the possibility of language. Hinge propositions, I argue, are rooted in these reactions; they point us to the limits of intelligibility of our concepts, though these limits are vague and inarticulable. In Part II, I discuss the practical syllogism and its validity. I argue that practical reasoning is distinct from theoretical reasoning and embodies a different standard of logical validity for inference. This standard is not strict and narrow, but creative and wide open; furthermore, it is an intrinsically ethical standard. Then, I advance my Linguistic Perspective on ethics, according to which human reactions provide the conditions for ethical normativity, just as they do for language. I argue that we can access ethical norms by reflecting on those linguistic concepts that are rooted in the most basic patterns of action, and by identifying the norms of behaviour that ensure the development of those concepts without contradiction. (shrink)

I argue that we can achieve certainty about some empirical propositions. When someone is having a migraine and attending to it, she can be certain that she is in pain. I show that examples intended to undermine claims of certainty or to raise doubts about the reliability of introspection do not touch such cases. Traditional foundationalists have held that epistemically certain beliefs can serve as the basis for all one’s other justified beliefs. This is not so, because those (...) beliefs that are certain are spread too thinly to serve as broad justificatory foundations. Certainty has a different role. The best explanation for the existence of epistemically certain empirical beliefs is experientialism, the view that nondoxastic sensory experiences can justify beliefs. Experientialism then offers a framework for showing how the stream of sensory experiences can provide an adequate basis for the justification of our ordinary beliefs about the external world. (shrink)

In the preface to On Certainty Anscombe and von Wright say that in 1949 Malcolm suggested to Wittgenstein to think again about Moore’s “Defense of Common Sense” (1925) and “Proof of an External World” (1939). Malcolm himself had written on the issue in “Defending Common Sense” (1949). In the preface to the Philosophical Investigations Wittgenstein quotes Nestroy saying that there is usually very little progress in philosophy. But I think some progress has been made from Moore and Malcolm to (...) Wittgenstein regarding skepticism. There is more awareness of practice and perspective and this opens the discussion in novel ways. But it also gives rise to new problems, in particular of morality and relativity. (shrink)

In this discussion note, I put forth an argument from the factivity of knowledge for the conclusion that knowledge is epistemic certainty. If this argument is sound, then epistemologists who think that knowledge is factive are thereby also committed to the view that knowledge is epistemic certainty.

Two seemingly contradictory tendencies have accompanied the development of the natural sciences in the past 150 years. On the one hand, the natural sciences have been instrumental in effecting a thoroughgoing transformation of social structures and have made a permanent impact on the conceptual world of human beings. This historical period has, on the other hand, also brought to light the merely hypothetical validity of scientific knowledge. As late as the middle of the 19th century the truth-pathos in the natural (...) sciences was still unbroken. Yet in the succeeding years these claims to certain knowledge underwent a fundamental crisis. For scientists today, of course, the fact that their knowledge can possess only relative validity is a matter of self-evidence. The present analysis investigates the early phase of this fundamental change in the concept of science through an examination of Hermann von Helmholtz's conception of science and his mechanistic interpretation of nature. Helmholtz (1821-1894) was one of the most important natural scientists in Germany. The development of this thoughts offers an impressive but, until now, relatively little considered report from the field of the experimental sciences chronicling the erosion of certainty. (shrink)

Although the impact of so-called “sponsorship bias” has been the subject of increased attention in the philosophy of science, what exactly constitutes its epistemic wrongness is still debated. In this paper, I will argue that neither evidential accounts nor social–epistemological accounts can fully account for the epistemic wrongness of sponsorship bias, but there are good reasons to prefer social–epistemological to evidential accounts. I will defend this claim by examining how both accounts deal with a paradigm case from medical epistemology, recently (...) discussed in a paper by Bennett Holman. I will argue that evidential accounts cannot adequately capture cases of sponsorship bias that involve the manufacturing of certainty because of their neutrality with respect to the role of non-epistemic values in scientific practice. If my argument holds, it further highlights the importance of integrating social and ethical concerns into epistemological analysis, especially in applied contexts. One can only properly grasp sponsorship bias as an epistemological problem if one resists the methodological tendency to analyze social, ethical, and epistemological issues in isolation from each other. (shrink)

The ongoing global pandemic of Covid-19 has exposed SARS-CoV-2 as a potent non-human actant that resists the joint scientific, public health and socio-political efforts to contain and understand both the virus and the illness. Yet, such a narrative appears to conceal more than it reveals. The seeming agentiality of the novel coronavirus is itself but one manifestation of the continuous destruction of biodiversity, climate change, socio-economic inequalities, neocolonialism, overconsumption and the anthropogenic degradation of nature. Furthermore, focusing on the virus – (...) an entity that holds an ambiguous status between the ‘living’ and ‘non-living’ – brings into question the issue of the agentiality of non/living matter. While the story of viral potency seems to get centre stage, overshadowing the complex and perverse entanglement of processes and phenomena which activated these potentials in the first place, the Covid-19 pandemic also becomes a prism that sheds light on the issues of environmental violence; social and environmental injustices; more-than-human agentiality; and ethico-political responses that the present situation may mobilise. -/- This article serves as a written record of joint conversations between artists and researchers in the working group ‘Non/Living Queerings’ that formed part of the online series of events ‘Braiding Friction’ organised by the research project Biofriction. The article strives to capture the collective effort of braiding and weaving a variety of situated perspectives, theoretical toolboxes, knowledges and experiences against the background of the ongoing Covid-19 pandemic. In particular, the text focuses on the issues of crisis, ‘amplification effect’, viral agency and the changing notions of humanity. (shrink)

This paper clarifies the philosophical connection between Al-Ghazali and Descartes, with the goal to articulate similarities and differences in their famous journeys from doubt to certainty. As such, its primary focus is on the chain of their reasoning, starting from their conceptions of truth and doubt arguments, until their arrival at truth. Both philosophers agreed on the ambiguous character of ordinary everyday knowledge and decided to set forth in undermining its foundations. As such, most scholars tend to agree that (...) the doubt arguments used by Descartes and Al-Ghazali are similar, but identify their departures from doubt as radically different: while Descartes found his way out of doubt through the cogito and so reason, Al-Ghazali ended his philosophical journey as a Sufi in a sheer state of passivity, waiting for the truth to be revealed to him by God. This paper proves this is not the case. Under close textual scrutiny and through the use of basic Husserlian-phenomenological concepts, I show that Al-Ghazali's position was misunderstood, thus disclosing his true philosophic nature. (shrink)