The aim of this paper is to analyse and develop how scepticism becomes an intelligible question starting from requirements that epistemologists themselves aim to endorse. We argue for and defend the idea that the root of scepticism is the underdetermination principle by articulating its specificitya respectable epistemic principle and by defending it against objections in current literature. This engagement offers a novel understanding of underdetermination-based scepticism. While most anti-sceptical approaches challenge scepticism by understanding it as postulating uneliminated scenarios of mass (...) deception, or as endorsing unnatural epistemic requirements, we argue here that both contentions are mistaken. Underdetermination-based scepticism targets our beliefs by issuing a genuine question about the rational support they enjoy. If we cannot establish that the sources of our beliefs provide them the required epistemic merit and authority, they lack non-arbitrary grounds. This has a sizable impact on what constitutes a satisfactory anti-sceptical strategy. Strategies that merely focus on the scenario-based aspect of scepticism, or on the truth-functional evaluation of our beliefs, are shown to miss the mark of the sceptical threat. The proposed analysis ultimately provides a shift in perspective concerning the character and reach of philosophical doubt. (shrink)

Epistemologists understand radical skepticism as arising from two principles: Closure and Underdetermination. Both possess intuitive prima facie support for their endorsement. Understanding how they engender skepticism is crucial for any reasonable anti-skeptical attempt. The contemporary discussion has focused on elucidating the relationship between them to ascertain whether they establish distinct skeptical questions and which of the two constitutes the ultimately fundamental threat. Major contributions to this debate are due to Brueckner, Cohen, and Pritchard. This contribution aims at defending Brueckner’s contention (...) that underdetermination expresses the fundamental skeptical threat and that the closure-based argument can ultimately be reduced to it, at least concerning skeptical contexts. This will be achieved by undermining Cohen’s objections to Brueckner on both counts. Cohen’s argument endorses a picture of evidential underdetermination, which, while apt for non-skeptical contexts, cannot be applied to radical skepticism. A comparison with a case of scientific underdetermination is developed to argue for this idea. Our argument is then applied to the principle equivalence issue and to objections against it. It is then shown how this analysis possesses a distinctive effect on our understanding of the skeptical threat and the assessment of successful anti-skeptical strategies. (shrink)

According to panpsychists, physical phenomena are, at bottom, nothing but experiential phenomena. One argument for this view proceeds from an alleged need for physical phenomena to have features beyond what physics attributes to them; another starts by arguing that consciousness is ubiquitous, and proposes an identification of physical and experiential phenomena as the best explanation of this alleged fact. The first argument assumes that physical phenomena have categorical natures, and the second that the world’s experience-causing powers or potentials underdetermine its (...) physical features. I argue that panpsychists are not entitled to these assumptions. (shrink)

I argue that, in at least one important sense, the hypothesis that you are a brain in a vat provides better explanations than the explanations provided by standard ways of interpreting our best scientific theories. This puts pressure on anyone who—like me!—wishes to resist taking this radical hypothesis seriously when doing science and scientifically-informed metaphysics. Insofar as our resistance is justified, it can’t be justified simply by claiming that the brain in a vast hypothesis is explanatorily impoverished.

I argue that the way the world appears to be plays an important role in standard scientific practice, and that therefore the way the world appears to be ought to play a similar role in metaphysics as well. I then show how the argument bears on a specific first-order debate in metaphysics – the debate over whether there are composite objects. This debate is often thought to be a paradigm case of a metaphysical debate that is largely insulated from scientific (...) considerations, and is often disparaged or avoided by naturalistically inclined metaphysicians as a result. My argument below shows that this attitude is a mistake. The way in which metaphysical debates can be informed by our best science is more complex and far-reaching than is often acknowledged in the literature. (shrink)

Various theorists contend that we may live in a computer simulation. David Chalmers in turn argues that the simulation hypothesis is a metaphysical hypothesis about the nature of our reality, rather than a sceptical scenario. We use recent work on consciousness to motivate new doubts about both sets of arguments. First, we argue that if either panpsychism or panqualityism is true, then the only way to live in a simulation may be as brains-in-vats, in which case it is unlikely that (...) we live in a simulation. We then argue that if panpsychism or panqualityism is true, then viable simulation hypotheses are substantially sceptical scenarios. We conclude that the nature of consciousness has wide-ranging implications for simulation arguments. (shrink)

According to the Nomological Argument, observed regularities in nature are best explained by an appeal to a supernatural being. A successful explanation must avoid two perils. Some explanations provide too little structure, predicting a universe without regularities. Others provide too much structure, thereby precluding an explanation of certain types of lawlike regularities featured in modern scientific theories. We argue that an explanation based in the creative, intentional action of a supernatural being avoids these two perils whereas leading competitors do not. (...) Although our argument falls short of a full defense, it does suggest that the Nomological Argument is worthy of philosophical attention. (shrink)

An important line of response to scepticism appeals to the best explanation. But anti-sceptics have not engaged much with work on explanation in the philosophy of science. I plan to investigate whether plausible assumptions about best explanations really do favour anti-scepticism. I will argue that there are ways of constructing sceptical hypotheses in which the assumptions do favour anti-scepticism, but the size of the support for anti-scepticism is small.

In this paper we don’t intend to show, against the sceptic, that most of our everyday beliefs about the external world are cases of knowledge. What we do try to show is that it is more rational to hold that most of such beliefs are actually cases of knowledge than to deny them this status, as the external world sceptic does. In some sense, our point of view is the opposite of Hume’s, who held that reason clearly favours scepticism about (...) the independent existence of an external world rather than common sense belief in such an independent existence. In arguing for the superior rationality of this common sense, Moorean view, we also take a fallibilist conception of knowledge to be rationally preferable to an infallibilist view of it. (shrink)

David. J. Chalmers examines eleven possible solutions to the meta-problem of consciousness, ‘the problem of explaining why we think that there is a problem of consciousness.’ The present paper argues that Chalmers overlooks an explanation that he has otherwise taken seriously, and which a number of philosophers, physicists, and computer scientists have taken seriously as well: the hypothesis that we are living in a computer simulation. This paper argues that a particular version of the simulation hypothesis is at least as (...) good of a solution to the meta-problem of consciousness as many explanations Chalmers considers, and may even be a better one—as it may be the best solution to a much broader meta-philosophical problem: the ‘meta-problem of everything’, the problem of explaining why our world has the quantum-mechanical, relativistic, and philosophical features it does. (shrink)

Laurence BonJour and more recently James Beebe have argued that the best way to defend the claim that abduction or inference to the best explanation is epistemically justified is the rationalist view that it is justified a priori. However, rationalism about abduction faces a number of challenges. This chapter focuses on one particular, highly influential objection, that there is no interpretation of probability available which is compatible with rationalism about abduction. The rationalist who wants to maintain a strong connection between (...) epistemic justification and probability would do best to rely on a Keynesian interpretation of probability. However, the latter is vulnerable to Ramsey’s famous criticism that we do not seem to perceive or be aware of such probabilities. The chapter argues that Ramsey’s criticism is unsuccessful, and that there are good reasons to be optimistic about our ability to have access to probabilities relevant to abductive inference. (shrink)

Should philosophers prefer simpler theories? Huemer (Philos Q 59:216–236, 2009) argues that the reasons to prefer simpler theories in science do not apply in philosophy. I will argue that Huemer is mistaken—the arguments he marshals for preferring simpler theories in science can also be applied in philosophy. Like Huemer, I will focus on the philosophy of mind and the nominalism/Platonism debate. But I want to engage with the broader issue of whether simplicity is relevant to philosophy.

Many who take a dismissive attitude towards metaphysics trace their view back to Carnap’s ‘Empiricism, Semantics and Ontology’. But the reason Carnap takes a dismissive attitude to metaphysics is a matter of controversy. I will argue that no reason is given in ‘Empiricism, Semantics and Ontology’, and this is because his reason for rejecting metaphysical debates was given in ‘Pseudo-Problems in Philosophy’. The argument there assumes verificationism, but I will argue that his argument survives the rejection of verificationism. The root (...) of his argument is the claim that metaphysical statements cannot be justified; the point is epistemic, not semantic. I will argue that this remains a powerful challenge to metaphysics that has yet to be adequately answered. (shrink)

An important line of response to scepticism appeals to the best explanation. But anti-sceptics have not engaged much with work on explanation in the philosophy of science. I plan to investigate whether plausible assumptions about best explanations really do favour anti-scepticism. I will argue that there are ways of constructing sceptical hypotheses in which the assumptions do favour anti-scepticism, but the size of the support for anti-scepticism is small.

Phenomenal conservatism is a popular theory of epistemic justification. Despite its popularity and the fact that some think that phenomenal conservatism can provide a complete account of justification, it faces several challenges. Among these challenges are the need to provide accounts of defeaters and inferential justification. Fortunately, there is hope for phenomenal conservatism. Explanationism, the view on which justification is a matter of explanatory considerations, can help phenomenal conservatism with both of these challenges. The resulting view is one that respects (...) the internalist character of phenomenal conservatism and its motivating intuitions while providing an intuitive and elegant account of both inferential justification and the justificatory impact of defeaters. (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)

Verschwörungstheorien (VTn) sind in der erkenntnistheoretischen Literatur wiederholt mit skeptischen Hypothesen verglichen worden: Beide entzögen sich der empirischen Überprüfung, indem sie sich gegen Gegenbelege immunisierten. Im Falle von VTn bestehe die Immunisierung darin, dass vermeintliche Gegenbelege ungeprüft auf Vertuschungs- oder Täuschungshandlungen der Verschwörer zurückgeführt würden. Eine genauere Rekonstruktion der Täuschungsthese und ein genauerer Blick auf die Immunisierungsthese fördern aber eine Reihe von Disanalogien zutage: Im Unterschied zu skeptischen Hypothesen behaupten VTn das eigene Szenario als real und schreiben die Täuschung nur (...) der Fremdgruppe zu. Damit besteht bei VTn auch nicht die für skeptische Hypothesen typische Symmetrie der Beleglage: Keine Partei diagnostiziert ein Patt, jede weist vielmehr die angeführten Belege der Gegenseite zurück. VTn entziehen die Täuschungsthese auch nicht jeder möglichen Überprüfung, wie es das Szenario des bösen Dämons tut, sondern kommen in unterschiedlichen Graden der Selbstimmunisierung vor. Die epistemischen Defizite von VTn und die Untugenden ihrer Verfechter treten deutlicher hervor, wenn man den Fokus von der Verschwörungsthese auf die Dynamik ihrer Verteidigung und ihre Ähnlichkeiten zu degenerierenden Forschungsprogrammen verschiebt. -/- In the epistemological literature, conspiracy theories (CTs) are often compared with skeptical hypotheses: Both are said to resist empirical refutation by immunising themselves against counterevidence. In the case of CTs, the trick is to explain away alleged counterevidence by cover-ups or deceptive acts on the part of the conspirators. However, a more precise reconstruction of the deception thesis and a closer look at the immunization thesis reveal a number of disanalogies: Unlike skeptical hypotheses, CTs claim their own scenario to be real, while attributing deception only to the outgroup. Correspondingly, CTs do not exhibit the balance of evidence typical of skeptical hypotheses: Neither party considers the evidence to be symmetrical, each rejects the evidence adduced by the opposing party. Unlike the evil demon scenario, the deception thesis in CTs is not entirely uncheckable. Rather, different CTs exhibit varying degrees of self-immunisation. The epistemic deficiencies of CTs and the epistemic vices of their proponents can be better brought out by shifting the focus from a CT’s claim to the dynamics of defending it and the similarities to degenerating research programmes. (shrink)

In this paper, I propose and defend a pair of necessary conditions on evidence-based knowledge which bear resemblance to the troubled sensitivity principles defended in the philosophical literature. We can think of the traditional principles as simple but inaccurate approximations of the new proposals. Insofar as the old principles are intuitive and used in scientific and philosophical contexts, but are plausibly false, there’s a real need to develop precise and correct formulations. These new renditions turned out to be more cautious, (...) so they won’t be able to do everything the old principled promised they could. For example, they respect closure for knowledge. But these sober formulations, or something like them, might be the best that we can do with respect to sensitivity. And there’s value in understanding the limits to these types of principles. (shrink)