In Minima Moralia, Adorno talks about a ‘messianic light’ which shines from beyond the corrupted world, offering the possibility of redemption from suffering. Theological statements like these have created significant controversy within the literature on Adorno, with interpreters like Hent de Vries and Peter Gordon arguing that the ‘messianic light’ depicts a transcendent negativity in line with negative theology. This is in opposition to the materialist interpretation, with interpreters like Jay Bernstein who oppose this reading, arguing that Adorno’s use of (...) messianic language is only a metaphorical means to express a negative approach to finite, material experience. In this article, I argue that an ambiguity concerning the source of redemption in Adorno’s work prevents either interpretation from being conclusive. Adorno vacillates between locating hope in sensuous experience or in spiritual negativity. In response, I offer a reading of Adorno’s notion of the object’s preponderance that fulfils both the materialist concern with concrete mediation as well as the theological notion that the messianic light cannot arise from the existing world. The experience of the retreat of the object’s preponderance explains our consciousness of a negative notion of redemption that transcends our current cultural circumstance. (shrink)

I present a novel anti-sceptical BIV argument by focusing on conditions on the production and use of the locative preposition ‘in’. I distinguish two uses of ‘in’—material and descriptive phenomenological—and I explain in what respect movement is central to the concept that our use of ‘in’ expresses. I go on to argue that a functionalist semantics of the intelligible use of ‘in’ demands a materialist philosophy of action in the spirit of G.E.M. Anscombe, but also why the structure of space (...) is not irrelevant either; appeal to the structure of space unsettles the causal-empirical assumptions that ground the picture of subjectivity and agency that the biv narrative assumes. Finally, I explain why a functionalist semantics demands a Naïve Realist metaphysics of perception, consistent with some of Putnam’s last writings on philosophy of perception. (shrink)

Several subjects are fully convinced that they are brains in vats whose experiences are hallucinatory. They confront a ‘skeptic’ who raises the possibility that they are not brains in vats who lack and hallucinate hands but ‘brains in skulls’ who have hands and see them. Familiar responses to skepticism are offered in support of the claim that the subjects know they do not have hands. The philosophical significance of this looking-glass approach to skepticism is also discussed. It is suggested that (...) these familiar responses to skepticism do not achieve anything because, if we begin from the assumption that we are brains in vats, we can employ those same responses to skepticism to support the claim that we know we do not have hands. One interlocutor argues that things are not so dismal. The main conversation is framed by a discussion among night watchmen at some sort of skepticism laboratory. (shrink)

There are brains in vats (BIVs) in the actual world. These “cerebral organoids” are roughly comparable to the brains of three-month-old foetuses, and conscious cerebral organoids seem only a matter of time. Philosophical interest in conscious cerebral organoids has thus far been limited to bioethics, and the purpose of this paper is to discuss cerebral organoids in an epistemological context. In doing so, I will argue that it is now clear that there are close possible worlds in which we (...) are BIVs. Not only does this solidify our intuitive judgement that we cannot know that we are not BIVs, but it poses a fundamental problem for both the neo-Moorean (i.e. safety-based) antisceptical strategy, which purports to allow us to know that we aren’t BIVs, and the safety condition on knowledge itself. Accordingly, this case is especially instructive in illustrating just how epistemologically relevant empirical developments can be. (shrink)

A sensible epistemologist may not see how she could know that she is not a brain in a vat ; but she doesn’t panic. She sticks with her empirical beliefs, and as that requires, believes that she is not a BIV. (She does not inferentially base her belief that she is not a BIV on her empirical knowledge—she rejects that ‘Moorean’ response to skepticism.) Drawing on the psychological literature on metacognition, I describe a mechanism that’s plausibly responsible for a sensible (...) epistemologist coming to believe she is not a BIV. I propose she thereby knows that she is not a BIV. The particular belief-forming mechanism employed explains why she overlooks this account of how she knows she is not a BIV, making it seem that there is no way for her to know it. I argue this proposal satisfactorily resolves the skeptical puzzle. (shrink)

Hilary Putnam’s BIV argument first occurred to him when ‘thinking about a theorem in modern logic, the “Skolem–Löwenheim Theorem”’ (Putnam 1981: 7). One of my aims in this paper is to explore the connection between the argument and the Theorem. But I also want to draw some further connections. In particular, I think that Putnam’s BIV argument provides us with an impressively versatile template for dealing with sceptical challenges. Indeed, this template allows us to unify some of Putnam’s most enduring (...) contributions to the realism/antirealism debate: his discussions of brains-in-vats, of Skolem’s Paradox, and of permutations. In all three cases, we have an argument which does not merely defeat the sceptic; it also shows us that we must reject some prima facie plausible philosophical picture. (shrink)

Recently it has been increasingly popular to argue that knowledge is the norm of belief. I present an argument against this view. The argument trades on the epistemic situation of the subject in the bad case. Notably, unlike with other superficially similar arguments against knowledge norms, knowledge normers preferred strategy of appealing to the distinction between permissibility and excusability cannot help them to rebut this argument.

Epistemic externalism offers one of the most prominent responses to the sceptical challenge. Externalism has commonly been interpreted as postulating a crucial asymmetry between the actual-world agent and their brain-in-a-vat counterpart: while the actual agent is in a position to know she is not envatted, her biv counterpart is not in a position to know that she is envatted, or in other words, only the former is in a position to know whether or not she is envatted. In this paper, (...) I argue that there is in fact no such asymmetry: assuming epistemic externalism, both the actual world agent and their biv counterpart are in a position to know whether or not they are envatted. After an introduction, I present the main argument. I examine to what extent the argument survives when one accepts additional externalist-friendly commitments: semantic externalism, a sensitivity condition on knowledge, and epistemic contextualism. Finally, I discuss the implications of my conclusion to a variety of debates in epistemology. (shrink)

The aim of this paper is to examine whether it would be advantageous to introduce knowledge norms instead of the currently assumed rational credence norms into the debate about decision making under normative uncertainty. There is reason to think that this could help us better accommodate cases in which agents are rationally highly confident in false moral views. I show how Moss’ view of probabilistic knowledge can be fruitfully employed to develop a decision theory that delivers plausible verdicts in these (...) cases. I also argue that, for this new view to be better than existing alternatives, it must adopt a particular solution to the new evil demon problem, which asks whether agents and their BIV-counterparts are equally justified. In order to get an attractive decision theory for cases of moral uncertainty, we must reject the claim that agents and their BIV-counterparts are equally justified. Moreover, the resulting view must be supplemented with a moral epistemology that explains how it is possible to be rationally morally uncertain. This is especially challenging if we assume that moral truths are knowable a priori. (shrink)

Skeptics claim that we know radically less than we think we do. For example, skeptics might claim that we have next to no knowledge of the past, the future, or other minds. Here we will consider the skeptical claim that we have next to no knowledge of the external world: the world of physical objects that we at least seem to perceive. One well-known argument in support of this claim appeals to the possibility of being a BIV: a brain in (...) a vat. According to the BIV Hypothesis, you are a mere BIV without a normal body. This of course means, among other things, that you don't have hands. The nerve endings of your brain are stimulated in a manner so sophisticated that the perfect illusion of a normal life is generated. Let's distinguish between the.. (shrink)

In this chapter, Pautz raises a puzzle about spatial experience for phenomenal internalists like Ned Block. If an accidental, lifelong brain-in-the-void (BIV) should have all the same experiences as you, it would have an experience as of items having various shapes, and be able to acquire concepts of those shapes, despite being cut off from real things with the shapes. Internalists cannot explain this by saying that BIV is presented with Peacocke-style visual field regions having various shapes, because these would (...) have to be non-physical sense data. They might instead explain this by saying that BIV “phenomenally represents” various shape properties. But since BIV lacks any interesting physical relations to shapes, this would imply that phenomenally representation is an irreducible relation. (shrink)

One interesting and potentially attractive feature of the sensitivity account of knowledge is that it not only preserves knowledge of ordinary propositions, but also concedes the skeptic's intuition that we do not know skeptical hypotheses do not obtain. This paper challenges the sensitivity‐based reply to the skeptic, advocated by Robert Nozick, among others. Sensitivity generates an implausibly bizarre result that although we do not know we are not brains in vats (because a belief to this effect is insensitive), a real (...) BIV who is in a much worse epistemic situation can sensitively believe that it is not in the good case. This result reveals a fundamental problem with the sensitivity conditional: its antecedent is not suitable for picking out possibilities that are relevant for our epistemic evaluation. I then offer a systematic explanation of why it is the safety account—the main competitor of sensitivity—that picks out a more suitable set of possibilities. A consequence of this comparison is that the safety account delivers an overall more satisfying reply to the skeptic than sensitivity does. (shrink)

According to MODERATISM, perceptual justification requires that one independently takes for granted propositional hinges like <There is an external world>, <I am not a brain in a vat (BIV)>, and so on. This view faces the truth problem: to offer an account of truth for hinges that is not threatened by skepticism. Annalisa Coliva has tried to solve the truth problem by combining the claim that external world propositions have a substantive truth property like correspondence with the claim that hinges (...) have a deflationary truth property. I argue that the resulting view cannot offer a coherent characterization of ‘skeptical switch scenarios’ while providing an effective anti-skeptical strategy. In a more positive vein, I defend an approach that combines a correspondence conception of truth with epistemological disjunctivism. (shrink)

Skeptics try to persuade us of our ignorance with arguments like the following: 1. I don’t know that I am not a handless brain-in-a-vat [BIV]. 2. If I don’t know that I am not a handless BIV, then I don’t know that I have hands. Therefore, 3. I don’t know that I have hands. The BIV argument is valid, its premises are intuitively compelling, and yet, its conclusion strikes us as absurd. Something has to go, but what? Contextualists contend that (...) an adequate solution to the skeptical problem must: (i) retain epistemic closure, (ii) explain the intuitive force of skeptical arguments by explaining why their premises initially seem so compelling, and (iii) account for the truth of our commonsense judgment that we do possess lots of ordinary knowledge. Contextualists maintain that the key to such a solution is recognizing that the semantic standards for ‘knows’ vary from context to context such that in skeptical contexts the skeptic’s premises are true and so is her conclusion; but in ordinary contexts, her conclusion is false and so is her first premise. Despite its initial attractiveness, the contextualist solution comes at a significant cost, for contextualism has many counterintuitive results. After presenting the contextualist solution, I identify a number of these costs. I then offer a noncontextualist solution that meets the adequacy constraint identified above, while avoiding the costs associated with contextualism. Hence, one of the principal reasons offered for adopting a contextualist theory of knowledge–its supposedly unique ability to adequately resolve the skeptical problem – is undermined. (shrink)

In this chapter, Pautz raises a puzzle about spatial experience for phenomenal internalists like Ned Block. If an accidental, lifelong brain-in-the-void (BIV) should have all the same experiences as you, it would have an experience as of items having various shapes, and be able to acquire concepts of those shapes, despite being cut off from real things with the shapes. Internalists cannot explain this by saying that BIV is presented with Peacocke-style visual field regions having various shapes, because these would (...) have to be non-physical sense data. They might instead explain this by saying that BIV “phenomenally represents” various shape properties. But since BIV lacks any interesting physical relations to shapes, this would imply that phenomenally representation is an irreducible relation. (shrink)

Pinillos’ Why We Doubt presents a powerful critique of such global skeptical assertions as “I don’t know I am not a brain-in-a-vat (biv)” by introducing a cognitive mechanism that is sensitive to error possibilities and a Bayesian rule of rationality that this mechanism is designed to approximate. This multifaceted argument offers a novel counter to global skepticism, contending that our basis for believing such premises is underminable. In this work, we engage with Pinillos’ adoption of Bayesianism, questioning whether the Bayesian (...) principle that he invokes truly does fail to generate the verdict that we don’t we aren’t biv s, contrary to what Pinillos asserts. Furthermore, we argue that Pinillos’ empirical argument is not empirical enough; we need a lot more empirical work if we are going to counter global skepticism and win over neutral bystanders. (shrink)

Nick Bostrom’s recently patched ‘‘simulation argument’’ (Bostrom in Philos Q 53:243–255, 2003; Bos- trom and Kulczycki in Analysis 71:54–61, 2011) purports to demonstrate the probability that we ‘‘live’’ now in an ‘‘ancestor simulation’’—that is as a simulation of a period prior to that in which a civilization more advanced than our own—‘‘post-human’’—becomes able to simulate such a state of affairs as ours. As such simulations under consid- eration resemble ‘‘brains in vats’’ (BIVs) and may appear open to similar objections, (...) the paper begins by reviewing objections to BIV-type proposals, specifically those due a presumed mad envatter. In counter example, we explore the motivating rationale behind current work in the development of psychologically realistic social simula- tions. Further concerns about rendering human cognition in a computational medium are confronted through review of current dynamic systems models of cognitive agency. In these models, aspects of the human condition are repro- duced that may in other forms be considered incomputable, i.e., political voice, predictive planning, and consciousness. The paper then argues that simulations afford a unique potential to secure a post-human future, and may be nec- essary for a pre-post-human civilization like our own to achieve and to maintain a post-human situation. Long-s- tanding philosophical interest in tools of this nature for Aristotle’s ‘‘statesman’’ and more recently for E.O. Wilson in the 1990s is observed. Self-extinction-level threats from State and individual levels of organization are compared, and a likely dependence on large-scale psychologically realistic simulations to get past self-extinction-level threats is projected. In the end, Bostrom’s basic argument for the conviction that we exist now in a simulation is reaffirmed. (shrink)

Putnam’s semantic argument against the BIV hypothesis and Sosa’s argument against dream skepticism based on the imagination model of dreaming share some important structural features. In both cases the skeptical option is supposed to be excluded because preconditions of its intelligibility are not fulfilled (affirmation and belief in the dream scenario, thought and reference in the BIV scenario). Putnam’s reasoning is usually interpreted differently, as a classic case of deception, but this feature is not essential. I propose to interpret BIV’s (...) utterances as cases of reference failure best captured by truth-value gaps. Both anti-skeptical strategies are then vulnerable to the same type of objections (how do we know what state we are in or how do we know what kind of language do we speak). (shrink)

Fallibilism is ubiquitous in contemporary epistemology. I argue that a paradox about knowledge, generated by considerations of truth, shows that fallibilism can only deliver knowledge in lucky circumstances. Specifically, since it is possible that we are brains‐in‐vats (BIVs), it is possible that all our beliefs are wrong. Thus, the fallibilist can know neither whether or not we have much knowledge about the world nor whether or not we know any specific proposition, and so the warrant of our knowledge‐claims is (...) much reduced and second‐order skepticism is generated. Since this is the case in both skeptical and everyday contexts, contextualism cannot resolve the paradox. (shrink)

If it works, I can use Putnam’s vat argument to show that I have not always been a brain-in-a-vat. It is widely thought that the vat argument is of no use against closure scepticism – that is, scepticism motivated by arguments that appeal to a closure principle. This is because, even if I can use the vat argument to show that I have not always been a BIV, I cannot use it to show that I was not recently envatted, and (...) it is thought that the claim that I am not justified in thinking that I was not recently envatted is all that the closure sceptic requires. In this paper I first argue that scenarios in which I have been recently envatted are inadequate for the sceptic’s purposes, and so the standard argument that the vat argument is of no use against closure scepticism fails. I then argue that it is not possible to revise the standard argument to meet my objection. I conclude that, if it works, I can use the vat argument as a defence against closure scepticism. (shrink)

Those of us who take skepticism seriously typically have two relevant beliefs: (a) it’s plausible (even if false) that in order to know that I have hands I have to be able to epistemically neutralize, to some significant degree, some skeptical hypotheses, such as the brain-in-a-vat (BIV) one; and (b) it’s also plausible (even if false) that I can’t so neutralize those hypotheses. There is no reason for us to also think (c) that the BIV hypothesis, for instance, is plausible (...) or probably true. In order to take skepticism seriously it’s sufficient to hold (a) and (b); one need not hold (c). Indeed, philosophers who accept (a) and (b) never endorse (c). Show me a philosopher who suspects that he is a brain in a vat and I’ll show you someone who is deranged! That’s one thing that bothers undergraduates in philosophy. They object: why on earth do some philosophers take the BIV hypothesis to pose any threat at all to our beliefs given that those very same philosophers think that there’s no real chance that the BIV hypothesis is true? Sure, the BIV hypothesis is formally inconsistent with my belief that I have hands, so if the former is true then my belief is false. But so what? Why should that bare inconsistency matter so much? Is this strange attitude amongst philosophers the result of some logic fetish infecting the philosophical community? It is sometimes said that the skeptical hypotheses are not only inconsistent with our beliefs but are explanatory of our experiences, which is supposed to make them more of a threat. But students aren’t fooled: although the skeptical hypotheses may attempt to explain why our experience is as it is, it’s the kind of attempt appropriate for science fiction movies that are all special effects and virtually no plot. No one with any sense of reality will take the evil demon hypothesis to be even tenuously explanatory. (shrink)

Davies and Wright have recently diagnosed the felt inadequacy of Moore’s response to the sceptic in terms of a failure of transmission of warrant. They argue that warrant fails to transmit across the following key inference: I have hands, if I have hands then I am not a BIV, so I am not a BIV, on the grounds that this inference cannot be used to rationally overcome doubt about its conclusion, and cannot strengthen one’s epistemic position with respect to the (...) conclusion. Here, for the sake of argument, I grant that the inference can neither rationally overcome doubt about its conclusion nor strengthen one’s epistemic position with respect to the conclusion, and examine whether, and in what way, this undermines.. (shrink)

The argument that has inspired much of the recent discussion of the logical relationship between these views is found in Putnam : If externalism is true, then if S were a brain in a vat, S’s utterances of the sentence “I am a brain in a vat” would not express the proposition that S is a brain in a vat. S’s use of the words “brain” and “vat” would not refer to a real brain or vat, just as, in a (...) Twin Earth-style thought experiment, the Twin Earthling cannot refer to water with his use of the term “water.” If we accept that generally we have knowledge of the contents of our utterances, then, if S knows that her utterances of “brain” and “vat” mean brain and vat, it will be possible for S to know that she is not a brain in a vat. For if S has authority with respect to the contents of her utterances, then she can know that her utterance, “I am not a brain in a vat,” refers to brains and vats. On externalism, since S would not refer to brains and vats if she were a brain in a vat, she could know by mere introspection that she is not a brain in a vat. In fact, S can come to know many arbitrary propositions about the external world simply by attending to the contents of her thoughts. For if externalism is true, she can argue, then certain empirical conditions must be satisfied if she is even to have the thoughts about the external world that she does; since she knows what she is thinking, she knows these empirical conditions are satisfied. Thus, if S knows that she is thinking about brains and vats, then she can know that she is not a brain in a vat ; for if she was a BIV, then she would not be thinking about brains and vats, but instead about electrical impulses or some such thing. The standard BIV argument against scepticism, therefore, cannot be correct. This line of argument can then be used to conclude more generally that scepticism is false; for the argument can be run with virtually any utterance or thought with empirical content. If S knows that she is thinking about trees, for example, then she can know that there are trees. (shrink)

SummaryA familiar sort of argument for skepticism about the external world appeals to the evidential similarity between what is presumed to be the normal case and the case where one is a brain in a vat . An argument from Putnam has been taken by many to provide an a priori refutation of this sort of skeptical argument. The question I propose to address in this paper is whether Putnam's argument affords us an a priori refutation of skeptical arguments that (...) appeal to the claim that one does not know that one is not a BIV. I will develop a negative answer to this question along two related fronts. Along the first front I defend against new criticisms the common position that the externalism on which Putnam's argument is based entails skepticism about the meanings of sentences in our language and the contents of our thoughts. I do not take this to be a refutation of externalism or externalist arguments; rather, I see this as a motivation to locate the difficulty with arguments for externalism. But if externalism is abandoned, of course, the anti‐skeptical argument it has widely been taken to support must be abandoned along with it. I will argue, however, that this is not a significant loss, because along a second front I will argue that externalism cannot be given a priori justification; it is therefore ill‐suited to ground an a priori refutation of BIV skepticism anyway. (shrink)

The paper is devoted to a discussion and critical evaluation of antisceptical arguments in epistemology that are based on causal theory of reference, with the special focus upon the revised version of the Hilary Putnam‘s Brain-in-a-Vat argument presented by Olaf Müller. Müller claims that his argument is based on the metaphysically neutral principles of semantic externalism and disquotation, however more thorough analysis of these principles and of the possibility to use them for antisceptical purposes reveals the flaw in his argument. (...) It seems that Müller reaches his conclusion by confusing the syntactically identical, though semantically distinct utterances in BIV language, non-BIV language, and metalanguage. The reconstruction and analysis of Müller‘s argument shows that his argument, provided that its premises are formulated carefully so as not to beg the question against the sceptic, fails to establish anything more than the original version provided by Putnam.Keywords: scepticism, Olaf Müller, semantic externalism, disquotation, brain-in-a-Vat. (shrink)

Contextualism is supposed to explain why the following argument for skepticism seems plausible: (1) I don’t know that I am not a bodiless brain-in-a-vat (BIV); (2) If I know I have hands, then I know I am not a bodiless BIV; (3) Therefore, I do not know I have hands. Keith DeRose claims that (1) and (2) are “initially plausible.” I claim that (1) is initially plausible only because of an implicit argument that stands behind it; it is not intuitively (...) plausible. The argument DeRose offers is based on the requirement of sensitivity, that is, on the idea that if you know something then you would not believe it if it were false. I criticize the sensitivity requirement thereby undercutting its support for (1) and the skeptical data that contextualism is meant to explain. While skepticism is not a plausible ground for contextualism, I argue that certain pragmatic considerations are. It’s plausible to think that to know something more evidence is required when more is at stake. The best way to handle skepticism is to criticize the arguments for it. We should not adopt contextualism as a means of accommodating skepticism even if there are other pragmatic reasons for being a contextualist about knowledge. (shrink)

Conflicts involving end-of-life care between healthcare providers (HCPs) and surrogate decision-makers (SDMs) have received sustained attention for more than a quarter of a century, with early studies demonstrating a frequency of HCP-SDM conflict in ICUs ranging from 32–78% of all admissions (Abbott et al. 2001; Breen et al. 2001; Studdert et al. 2003; Azoulay et al. 2009). More recent studies not only acknowledge the persistence of clinical conflict in end-of-life care (Leland et al. 2017), but they have begun to focus (...) on the ways in which these conflicts escalate to verbal or physical violence in the ICU (Slack et al. 2023; Bass et al. 2024; Berger et al. 2024; Sjöberg et al. 2024). I will argue that part of the explanation for the persistence–and even escalation–of ICU disputes is the incommensurable value systems held by many conflicting HCPs and SDMs. I will argue that a common value system among HCPs can be understood as a “Best Interest Values” (BIV) hierarchy, which I will argue is irreconcilable with the set of “Life-Continuation Values” (LCV) held by a sizable minority of families in the United States. I argue this values-conflict undergirds many ICU disputes. If I am correct that an incommensurable value system underlies many ICU conflicts, then it is not just ineffectual for HCPs to impose their BIV system on LCV families, but also wrong given the American commitment to values pluralism. I conclude that the way to navigate continuous ICU surrogate wars is for BIV-focused healthcare institutions to engage more constructively with LCV stakeholders. (shrink)

Dogmatists often exploit the skeptical argument based on the brains-in-a-vat scenario as a test case for their epistemological enterprises. I argue that this ‘argument’ does not deserve our attention, so it should not be used as a test case. I first show that the possibilities of empirical knowledge and of skeptical scenarios are inconsistent. If so, the BIV-skeptic must make the case for preferring such scenarios over the possibility of empirical knowledge. The central argument of my paper is that the (...) BIV-skeptic can neither rely on any selection principle for this purpose, nor can she claim that she needs no such principle. Then I will show that we can even dispense with the Inconsistency Thesis: if the skeptic wishes, she may allow for the possibility of empirical knowledge. The essay concludes with considering the morals of the above argument for the dogmatist endeavor. (shrink)

A well known skeptical paradox rests on the claim that we lack warrant to believe that we are not brains in a vat. The argument for that claim is the apparent impossibility of any evidence or argument that we are not BIVs. Many contemporary philosophers resist this argument by insisting that we have a sort of warrant for believing that we are not BIVs that does not require having any evidence or argument. I call this view ‘New Rationalism’. (...) I argue that New Rationalists are committed to there being some evidence or argument for believing that we are not BIVs anyway. Therefore, New Rationalism, since its appeal is that it purportedly avoids the problematic commitment to such evidence or argument, undermines its own appeal. We cannot avoid the difficult work of coming up with evidence or argument by positing some permissive sort of warrant. (shrink)

This paper aims to motivate a scepticism about scepticism in contemporary epistemology. I present the sceptic with a dilemma: On one parsing of the BIV (brain-in-a-vat) scenario, the second premise in a closure-based sceptical argument will turn out false, because the scenario is refutable; on another parsing, the scenario collapses into incoherence, because the sceptic cannot even save the appearances. I discuss three different ways of cashing out the BIV scenario: ‘Recent Envatment’ (RE), ‘Lifelong Envatment’ (LE) and ‘Nothing But Envatment’ (...) (NBE). I show that RE scenarios are a kind of ‘local’ sceptical scenario that does not pose a significant threat to the possibility of perceptual knowledge as such. I then go on to consider the more radical (or global) LE and NBE scenarios, which do undermine the possibility of perceptual knowledge of an ‘external’ world by positing that it is conceivable that one has always been envatted and, hence, trapped in a ‘global’ illusion. I start by assuming that we could be in such a scenario (LE or NBE) and then spell out what we would need to presuppose for such scenarios to be capable of being actual. Drawing on some central insights from Wittgenstein’s anti-private language considerations, I show that the truth of a global scepticism would presuppose the possibility of a private ‘vat-language’, a notion that cannot be rendered coherent. But, if so, then neither can the sceptical scenarios that presuppose such a conception. (shrink)

An orthodox sceptical hypothesis claims that one’s belief that “I am not a brain-in-a-vat (BIV)” (or any other ordinary anti-sceptical belief) is insensitive. A form of sensitivity-based scepticism, can thus be constructed by combining this orthodox hypothesis with the sensitivity principle and the closure principle. Unlike traditional solutions to the sensitivity-based sceptical problem, this paper will propose a new solution—one which does not reject either closure or sensitivity. Instead, I argue that sceptics’ assumption that one’s ordinary anti-sceptical beliefs are insensitive (...) will give rise to self-contradiction. The orthodox sceptical hypothesis is thus revealed to be incoherent and arbitrary. Given that there is no coherent reason to presuppose our ordinary anti-sceptical beliefs to be insensitive, the argument for sensitivity-based scepticism can thus be blocked at a lower epistemological cost. (shrink)

In Reason, Truth and History, Putnam provides an influential argument for the materialist view that the supposition that we are all “actually” brains in a vat [BIV’s] is “necessarily false”. Putnam admits that his argument, inspired by insights in Wittgenstein’s later views, is “unusual”, but he is certain that it is a correct. He argues that the claim that we are BIV’s is self-refuting because, if we actually are BIV’s, then we cannot refer to real physical things like vats. Although (...) the present author agrees, fundamentally, with Heidegger’s view that we are essentially “in a world”, and, therefore, with Putnam’s conclusion that we cannot possibly be BIV’s, the paper argues that Putnam’s argument is fallacious. The proper conclusion to draw from Putnam’s argument is that asserting that one is a BIV is beyond the limits of a BIV’s language. That is, Putnam only shows that if we actually are BIV’s, then we cannot think or assert either that we are or that we are not BIV’s. It does not show that we are not “actually” BIV’s. The cogency of this criticism is illustrated with a concrete “science-fiction” example. (shrink)

According to Duncan Pritchard, there are two kinds of radical sceptical problem; the closure-based problem, and the underdetermination-based problem. He argues that distinguishing these two problems leads to a set of desiderata for an anti-sceptical response, and that the way to meet all of these desiderata is by supplementing a form of Wittgensteinian contextualism with disjunctivist views about factivity. I agree that an adequate response should meet most of the initial desiderata Pritchard puts forward, and that some version of Wittgensteinian (...) contextualism shows the most promise as a starting point for this, but I argue, contra Pritchard, that the addition of disjunctivism is unnecessary and potentially counter-productive. If we draw on lessons from Michael Williams's inferential contextualism then it is both possible, and preferable, to meet the most important of Pritchard's desiderata, undercutting both closure-based and underdetermination-based sceptical problems in a unified way, without the need to resort to disjunctivism. (shrink)

There is an epistemological skepticism that I might be dreaming now, or I might be a brain in a vat (BIV). There is also a demonstration that derives the skeptical conclusion about knowledge of the external world from the premise C1, i.e., I do not know “I am not dreaming (not a BIV) now.” Pessimistic critics (e.g., F. Strawson, B. Stroud) consider that the refutation of C1 is impossible, whereas others have attempted the direct refutation of C1 (e.g., G. E. (...) Moore, H. Putnam, C. Wright), and some (e.g., F. Dretske, R. Nozick) have attempted to refute the closure principle of knowledge used in the demonstration while permitting the validity of C1. Another scholar, M. Williams, maintains that the skeptical demonstration is true only if we presuppose the epistemological premise that we choose to accept or reject at will. It seems that most critics tend to adopt a strategy that allows them to effectively avoid the skeptical consequence, thereby conceding the validity of C1. However, it is difficult to say whether their attempts succeeded, and in my opinion, they are indeed unsuccessful. This is because their concession to Descartes’ argument is insufficient. Their lack of success could also stem from the incompletion of Descartes’ own methodological doubt. The somewhat paradoxical‐sounding aim of this thesis is to show that the skeptical paradox about knowledge can be dissolved only if the Cartesian skepticism is extended far beyond the endpoint of his attempt. The argument of this thesis is based on the important arguments of Wittgenstein's On Certainty （OC）. (shrink)

Skeptics try to persuade us of our ignorance with arguments like the following: 1. I don't know that I am not a handless brain-in-a-vat [BIV]. 2. If I don't know that I am not a handless BIV, then I don't know that I have hands. Therefore, 3. I don't know that I have hands. The BIV argument is valid, its premises are intuitively compelling, and yet, its conclusion strikes us as a absurd. Something has to go, but what? Contextualists contend (...) that an adequate solution to the skeptical problem must: (i) retain epistemic closure, (ii) explain the intuitive force of skeptical arguments by explaining why their premises initially seem so compelling, and (iii) account for the truth of our commonsense judgment that we do possess lots of ordinary knowledge. Contextualists maintain that the key to such a solution is recognizing that the semantic standards for 'knows' vary from context to context such that in skeptical contexts the skeptic's premises are true and so is her conclusion; but in ordinary contexts, her conclusion is false and so is her first premise. Despite its initial attractiveness, the contextualist solution comes at a significant cost, for contextualism has many counterintuitive results. After presenting the contextualist solution, I identify a number of these costs. I then offer a noncontextualist solution that meets the adequacy constraint identified above, while avoiding the costs associated with contextualism. Hence, one of the principal reasons offered for adopting a contextualist theory of knowledge -- its supposedly unique ability to adequately resolve the skeptical problem -- is undermined. (shrink)

The dream sceptic argues that our ordinary beliefs are not justified because we cannot know that we have not always been dreaming. This is the Always Dreaming Hypothesis (ADH). I develop the traditional coherence objection to dream scepticism and argue that the coherence objection can be reformulated in a way that makes it both plausible and defensible. Considerations about the incoherence of dreams can be given probabilistic expression in a way that shows ADH to be highly improbable. Given the evidence (...) of coherence, ADH can be rationally rejected. Even if ADH is augmented with causal information sufficient to account for the coherence and order of conscious experience, the resulting dream scepticism would then reduce to a BIV-type scepticism and thus fail to possess independent sceptical force. (shrink)

Goldberg 2016 is a collection of papers dedicated to Putnam’s (1981) brain in a vat (‘BIV’) scenario. The collection divides into three parts, though the issues are inter-connected. Putnam uses conceptual tools from philosophy of language in order to establish theses in epistemology and metaphysics. Putnam’s BIV is considered a contemporary version of Descartes’s skeptical argument of the Evil Genius, but I argue that deception (the possibility of having massively false belief) is not essential, externalism does all the anti-skeptical work. (...) The largest section in the collection covers Putnam’s model-theoretic argument (MTA) against metaphysical realism (MR) and its connections with the brain in vat argument (BVA). There are two camps—unifiers (there is a deep connection in Putnam’s thoughts on BVA, MTA and MR) and patchwork theorists and I try to provide some support for the second camp. All of the papers in the collection are discussed and the anti-skeptical potential of BVA is critically assessed. (shrink)

This paper defends the legitimacy of semantical responses to certain skeptical challenges, with a particular focus on Putnam’s treatment of a particular version of Brain-in-Vat skepticism. It argues that while Putnam’s argument does not provide a general reply to Brain-in-Vat skepticism, the general approach it exemplifies is actually crucial in replying to other skeptical challenges that are otherwise hard to rebut.

Failure to recognize the "realistic" motivations for Putnam's commitment to internal realism has led to a widely shared misunderstanding of Putnam's arguments against metaphysical realism. Realist critics of these arguments frequently offer rebuttals that fail to confront his arguments. Simply put, Putnam's arguments --the brains in a vat argument as well as the model-theoretic argument -- are "reductios" that are intended to show that "metaphysical realism itself is not sufficiently realistic". If that claim can be substantiated then Putnam can go (...) on to argue that his own view is, by comparison, more realistic than metaphysical realism. (shrink)