Despite its uniform appearance, the cerebellar cortex is highly heterogeneous in terms of structure, genetics and physiology. Purkinje cells (PCs), the principal and sole output neurons of the cerebellar cortex, can be categorized into multiple populations that differentially express molecular markers and display distinctive physiological features. Such features include action potential rate, but also their propensity for synaptic and intrinsic plasticity. However, the precise molecular and genetic factors that correlate with the differential physiological properties of PCs remain elusive. In this (...) article, we provide a detailed overview of the cellular mechanisms that regulate PC activity and plasticity. We further perform a pathway analysis to highlight how molecular characteristics of specific PC populations may influence their physiology and plasticity mechanisms. (shrink)

We can understand viewed scenes and extract task-relevant information within a few hundred milliseconds. This process is generally supported by three cortical regions that show selectivity for scene images: parahippocampal place area (PPA), medial place area (MPA) and occipital place area (OPA). Prior studies have focused on the visual information each region is responsive to, usually within the context of recognition or navigation. Here, we move beyond these tasks to investigate gaze allocation during scene viewing. Eye movements rely on a (...) scene’s visual representation to direct saccades, and thus foveal vision. In particular, we focus on the contribution of OPA, which is i) located in occipito-parietal cortex, likely feeding information into parts of the dorsal pathway critical for eye movements, and ii) contains strong retinotopic representations of the contralateral visual field. Participants viewed scene images for 1034 ms while their eye movements were recorded. On half of the trials, a 500 ms train of five transcranial magnetic stimulation (TMS) pulses was applied to the participant’s cortex, starting at scene onset. TMS was applied to the right hemisphere over either OPA or the occipital face area (OFA), which also exhibits a contralateral visual field bias but shows selectivity for face stimuli. Participants generally made an overall left-to-right, top-to-bottom pattern of eye movements across all conditions. When TMS was applied to OPA, there was an increased saccade latency for eye movements toward the contralateral relative to the ipsilateral visual field after the final TMS pulse (400ms). Additionally, TMS to the OPA biased fixation positions away from the contralateral side of the scene compared to the control condition, while the OFA group showed no such effect. There was no effect on horizontal saccade amplitudes. These combined results suggest that OPA might serve to represent local scene information that can then be utilized by visuomotor control networks to guide gaze allocation in natural scenes. (shrink)

Williams Syndrome is a developmental disorder that is characterized by cardiovascular problems, particular facial features and several typical behavioral and neurological abnormalities. In Williams Syndrome patients, a heterozygous deletion is present of a region on chromosome 7q11.23 (the Williams Syndrome critical region), which spans approximately 20 genes. Two of these genes encode proteins that regulate dynamic aspects of the cytoskeleton of the cell, either via the actin filament system (LIM kinase 1, or LIMK1), or through the microtubule network (cytoplasmic linker (...) protein of 115 kDa, or CLIP‐115). The recent findings that knockout mice lacking LIMK1 or CLIP‐115 have distinct neurological and behavioural phenotypes, indicates that cytoskeletal defects might play a role in the development of neurological symptoms in Williams Syndrome patients. In this review, we discuss the properties of LIMK and CLIP family proteins, their function in the regulation of the actin and microtubule cytoskeletal systems, respectively, and the relationship with neurodevelopmental aspects of Williams Syndrome. BioEssays 26:141–150, 2004. © 2004 Wiley Periodicals, Inc. (shrink)

This book examines the hypothesis of "direct compositionality", which requires that semantic interpretation proceed in tandem with syntactic combination. Although associated with the dominant view in formal semantics of the 1970s and 1980s, the feasibility of direct compositionality remained unsettled, and more recently the discussion as to whether or not this view can be maintained has receded. The syntax-semantics interaction is now often seen as a process in which the syntax builds representations which, at the abstract level of logical form, (...) are sent for interpretation to the semantics component of the language faculty. In the first extended discussion of the hypothesis of direct compositionality for twenty years, this book considers whether its abandonment might have been premature and whether in fact direct compositionality is not after all a simpler and more effective conception of the grammar than the conventional account of the syntax-semantics interface in generative grammar. It contains contributions from both sides of the debate, locates the debate in the setting of a variety of formal theories, and draws on examples from a range of languages and a range of empirical phenomena. (shrink)

Next SectionIn this remark, I first show that a Lewis–Kratzer–von Fintel style semantics of conditionals and modals (Lewis 1973; Kratzer 1991a, b; von Fintel 1994; a.o.) together with the downward-entailing-based (DE-based) approach to the licensing of negative polarity items (NPIs) incorrectly predicts that NPIs are ungrammatical in the if-clause of a conditional with a possibility modal in the main clause (i.e., a conditional of the form if p, ◊q; henceforth, CPM; e.g., If John has ever been to Paris, he might (...) become a good chef). I then list three possible solutions to this problem to be explored in future work. (shrink)

The Neo-Moorean Deduction (I have a hand, so I am not a brain-in-a-vat) and the Zebra Deduction (the creature is a zebra, so isn’t a cleverly disguised mule) are notorious. Crispin Wright, Martin Davies, Fred Dretske, and Brian McLaughlin, among others, argue that these deductions are instances of transmission failure. That is, they argue that these deductions cannot transmit justification to their conclusions. I contend, however, that the notoriety of these deductions is undeserved. My strategy is to clarify, attack, defend, (...) and apply. I clarify what transmission and transmission failure really are, thereby exposing two questionable but quotidian assumptions. I attack existing views of transmission failure, especially those of Crispin Wright. I defend a permissive view of transmission failure, one which holds that deductions of a certain kind fail to transmit only because of premise circularity. Finally, I apply this account to the Neo-Moorean and Zebra Deductions and show that, given my permissive view, these deductions transmit in an intuitively acceptable way—at least if either a certain type of circularity is benign or a certain view of perceptual justification is false. (shrink)

Looking out the window, I see that it's raining outside. Do I know that it’s raining outside? According to proponents of the Entailment Thesis, I do. If I see that p, I know that p. In general, the Entailment Thesis is the thesis that if S perceives that p, S knows that p. But recently, some philosophers (McDowell 2002, Turri 2010, Pritchard 2011, 2012) have argued that the Entailment Thesis is false. On their view, we can see p and not (...) know that p. In this paper, I argue that their arguments are unsuccessful. (shrink)

Seminal work in moral neuroscience by Joshua Greene and colleagues employed variants of the well-known trolley problems to identify two brain networks which compete with each other to determine moral judgments. Greene interprets the tension between these brain networks using a dual process account which pits deliberative reason against automatic emotion-driven intuitions: reason versus passion. Recent neuroscientific evidence suggests, however, that the critical tension that Greene identifies as playing a role in moral judgment is not so much a tension between (...) reason and passion, but a tension between distinct forms of deliberative reasoning: analytic versus empathetic. In this paper we present results from several new studies supporting this alternative hypothesis. (shrink)

What should we do when faced with powerful theoretical arguments that support a severe change in our personal beliefs and commitments? For example, what should new parents do when confronted by unanswered anti-natalist arguments, or two lovers vexed by social theory that apparently undermines love? On the one hand, it would be irrational to ignore theory just because it’s theory; good theory is evidence, after all. On the other hand, factoring in theory can be objectifying, or risks unraveling one's life, (...) fracturing one's identity or social relations. Sometimes, then, following the evidence where it apparently leads would mean not merely changing what we think but who we are. Some might say that there’s something right about the thought that theory can bear on what we ought to believe, it’s just that when we work with full beliefs, only then do we seriously risk having to substantially alter our doxastic economy when pressed by exceptional theoretical arguments. When we work with partial beliefs, however, this risk is greatly diminished. Others will say that we can advocate or champion revisionary positions whilst rationally retaining our pre-theoretical personal convictions. Still others will argue that we should adopt a Moorean posture towards the revisionary arguments. I argue that each response is inadequate, and argue instead that we are permitted to bracket certain kinds of theoretical evidence against our beliefs because of the personal and ethical risks born out of giving them serious consideration. In turn, some of philosophy's doxastic influence is constrained by its attendant ethical risks: the personal enjoys a partial insulation from the theoretical. I close by addressing what this means for practicing philosophers. (shrink)

Is radical skepticism ethically problematic? This paper argues that it is. Radical skepticism’s strong regulation of our doxastic economy results in us having to forego doxastic commitments that we owe to others. Whatever skepticism’s epistemic defects, it is ethically defective. In turn, I defend Moralism, the view that the kind of extreme doubt characteristic of radical skepticism is a serious moral and eudaimonic weakness of radical skeptical epistemology. Whether this means that skepticism is false or incorrect, however, is a further (...) claim that Moralists may or may not accept. I distinguish between an encroachment and abrogation version of the view, and show how each one bears on radical skepticism. In either case, Moralism makes our beliefs less vulnerable to radical revision. The paper concludes with some exploratory reflections on whether the argument can be extended to show that radical skepticism is politically problematic, even risking injustice. (shrink)

This article argues for a revised best system account of laws of nature. David Lewis’s original BSA has two main elements. On the one hand, there is the Humean base, which is the totality of particular matters of fact that obtain in the history of the universe. On the other hand, there is what I call the ‘nomic formula’, which is a particular operation that gets applied to the Humean base in order to output the laws of nature. My revised (...) account focuses on this latter element of the view. Lewis conceives of the nomic formula as a balance of simplicity and strength, but I argue that this is a mistake. Instead, I motivate and develop a different proposal for the standards that figure into the nomic formula, and I suggest a rationale for why these should be the correct standards. Specifically, I argue that the nomic formula should be conceived as a collection of desiderata designed to generate principles that are predictively useful to creatures like us. The resulting view—which I call the ‘best predictive system’ account of laws—is thus able to explain why scientists are interested in discovering the laws, and it also gives rise to laws with the sorts of features that we find in actual scientific practice 1Introduction2The LOPP3A Problem with Lewis's Formula4A Pragmatic Account of the Nomic Formula 4.1Informative dynamics4.2Wide applicability4.3Spatial locality4.4Temporal locality4.5Spatial, temporal, and rotational symmetries4.6Predictively useful properties4.7Simplicity4.8Recap5 Conclusion. (shrink)

What is the nature of deep disagreement? In this paper, I consider two similar albeit seemingly rival answers to this question: the Wittgensteinian theory, according to which deep disagreements are disagreements over hinge propositions, and the fundamental epistemic principle theory, according to which deep disagreements are disagreements over fundamental epistemic principles. I assess these theories against a set of desiderata for a satisfactory theory of deep disagreement, and argue that while the fundamental epistemic principle theory does better than the Wittgensteinian (...) theory on this score, the fundamental epistemic principle theory nevertheless struggles to explain the variety of deep disagreement. (shrink)

Users of psychedelic drugs often report that their sense of being a self or ‘I’ distinct from the rest of the world has diminished or altogether dissolved. Neuroscientific study of such ‘ego dissolution’ experiences offers a window onto the nature of self-awareness. We argue that ego dissolution is best explained by an account that explains self-awareness as resulting from the integrated functioning of hierarchical predictive models which posit the existence of a stable and unchanging entity to which representations are bound. (...) Combining recent work on the ‘integrative self' and the phenomenon of self-binding with predictive processing principles yields an explanation of ego dissolution according to which self-representation is a useful Cartesian fiction: an ultimately false representation of a simple and enduring substance to which attributes are bound which serves to integrate and unify cognitive processing across levels and domains. The self-model is not a mere narrative posit, as some have suggested; it has a more robust and ubiquitous cognitive function than that. But this does not mean, as others have claimed, that the self-model has the right attributes to qualify as a self. It performs some of the right kinds of functions, but it is not the right kind of entity. Ego dissolution experiences reveal that the self-model plays an important binding function in cognitive processing, but the self does not exist. (shrink)

Various questions arise in semantic analysis concerning the nature of types. These questions include whether we need types in a semantic theory, and if so, whether some version of simple type theory (STT, Church 1940) is adequate or whether a richer more flexible theory is required to capture our semantic intuitions. Propositions and propositional attitudes can be represented in an essentially untyped first-order language, provided a sufficiently rich language of terms is adopted. In the absence of rigid typing, care needs (...) to be taken to avoid the paradoxes, for example by constraining what kinds of expressions are to be interpreted as propositions (Turner 1992). But the notion of type is ontologically appealing. In some respects, STT seems overly restrictive for natural language semantics. For this reason it is appropriate to consider a system of types that is more flexible than STT, such as a Curry-style typing (Curry & Feys 1958). Care then has to be taken to avoid the logical paradoxes. Here we show how such an account, based on the Property Theory with Curry Types (PTCT, Fox & Lappin 2005), can be formalised within Typed Predicate Logic (TPL, Turner 2009). This presentation provides a clear distinction between the classes of types that are being used to (i) avoid paradoxes (ii) allow predicative polymorphic types. TPL itself provides a means of expressing PTCT in a uniform language. (shrink)

Some understand Stein’s “Yes, but…” as an entry in the realism—instrumentalism debate (RID) itself, albeit one dissatisfied with then-extant positions. In this paper, however, I argue the opposite: Stein’s conception of science and his approach to its history and philosophy actually preclude the RID. First, I characterize Stein as persistently attending to his own historical and philosophical methods. I then describe his conception of science as both a dialectic and an enterprise, and I draw from this conception several conclusions about (...) the relations between science and its history and philosophy. Finally, I provide a reading of “Yes, but…” that follows from Stein’s conception of science. On this reading, the RID is either irrelevant to or wrong of science and, moreover, distracts from a legitimate inquiry. I conclude by interpreting Stein’s remark that there is ``no difference that makes a difference’’ between a cogent and enlightened realism and a sophisticated instrumentalism. (shrink)

This paper explores the application of hinge epistemology to deep disagreement. Hinge epistemology holds that there is a class of commitments—hinge commitments—which play a fundamental role in the structure of belief and rational evaluation: they are the most basic general ‘presuppositions’ of our world views which make it possible for us to evaluate certain beliefs or doubts as rational. Deep disagreements seem to crucially involve disagreements over such fundamental commitments. In this paper, I consider pessimism about deep disagreement, the thesis (...) that such disagreements are rationally irresolvable, and ask whether the Wittgensteinian account of deep disagreement—according to which such disagreements are disagreements over hinge commitments—provides adequate support for pessimism. I argue that the answer to this question depends on what hinge commitments are and what our epistemic relation to them is supposed to be. I argue for two core claims. First, that non-epistemic theories of hinge commitments provide adequate support for pessimism. Nevertheless, such theories have highly implausible consequences in the context of deep disagreement. Secondly, at least one epistemic theory of hinge commitments, the entitlement theory, permits optimism about such disagreements. As such, while hinge epistemology is mainly pessimistic about deep disagreement, it doesn’t have to be. (shrink)

This paper explores the application of hinge epistemology to deep disagreement. Hinge epistemology holds that there is a class of commitments—hinge commitments—which play a fundamental role in the structure of belief and rational evaluation: they are the most basic general ‘presuppositions’ of our world views which make it possible for us to evaluate certain beliefs or doubts as rational. Deep disagreements seem to crucially involve disagreements over such fundamental commitments. In this paper, I consider pessimism about deep disagreement, the thesis (...) that such disagreements are rationally irresolvable, and ask whether the Wittgensteinian account of deep disagreement—according to which such disagreements are disagreements over hinge commitments—provides adequate support for pessimism. I argue that the answer to this question depends on what hinge commitments are and what our epistemic relation to them is supposed to be. I argue for two core claims. First, that non-epistemic theories of hinge commitments provide adequate support for pessimism. Nevertheless, such theories have highly implausible consequences in the context of deep disagreement. Secondly, at least one epistemic theory of hinge commitments, the entitlement theory, permits optimism about such disagreements. As such, while hinge epistemology is mainly pessimistic about deep disagreement, it doesn’t have to be. (shrink)

What is the epistemological significance of deep disagreement? Part I explored the nature of deep disagreement, while Part II considers its epistemological significance. It focuses on two core problems: the incommensurability and the rational resolvability problems. We critically survey key responses to these challenges, before raising worries for a variety of responses to them, including skeptical, relativist, and absolutist responses to the incommensurability problem, and to certain steadfast and conciliatory responses to the rational resolvability problem. We then pivot to the (...) ethical and political dimensions of deep disagreement. We focus on whether an unwillingness to engage with positions one considers to be immoral or repugnant might be good, and conclude with some reflections on the moral risks of engagement. (shrink)

Conflicting accounts of the role of mathematics in our physical theories can be traced to two principles. Mathematics appears to be both (1) theoretically indispensable, as we have no acceptable non-mathematical versions of our theories, and (2) metaphysically dispensable, as mathematical entities, if they existed, would lack a relevant causal role in the physical world. I offer a new account of a role for mathematics in the physical sciences that emphasizes the epistemic benefits of having mathematics around when we do (...) science. This account successfully reconciles theoretical indispensability and metaphysical dispensability and has important consequences for both advocates and critics of indispensability arguments for platonism about mathematics. (shrink)

One of the main challenges confronting Humean accounts of natural law is that Humean laws appear to be unable to play the explanatory role of laws in scientific practice. The worry is roughly that if the laws are just regularities in the particular matters of fact (as the Humean would have it), then they cannot also explain the particular matters of fact, on pain of circularity. Loewer (2012) has defended Humeanism, arguing that this worry only arises if we fail to (...) distinguish between scientific and metaphysical explanations. However, Lange (2013, 2018) has argued that scientific and metaphysical explanations are linked by a transitivity principle, which would undercut Loewer's defense and re-ignite the circularity worry for the Humean. I argue here that the Humean has antecedent reasons to doubt that there are any systematic connections between scientific and metaphysical explanations. The reason is that the Humean should think that scientific and metaphysical explanation have disparate aims, and therefore that neither form of explanation is beholden to the other in its pronouncements about what explains what. Consequently, the Humean has every reason to doubt that Lange's transitivity principle obtains. (shrink)

The moral enhancement of humans by biological or genetic means has recently been urged as a response to the pressing concerns facing human civilization. In this paper, I argue that proponents of biological moral enhancement have misrepresented the facts of human moral psychology. As a result, the likely effectiveness of traditional methods of moral enhancement has been underestimated, relative to biological or genetic means. I review arguments in favor of biological moral enhancement and argue that the complexity of moral psychology (...) raises serious problems for such interventions. I offer a programmatic sketch of the ways in which our improved understanding of moral psychology can help facilitate more traditional methods of moral enhancement. I conclude that the best response to the dangers faced by human civilization is the continued use of traditional methods of moral enhancement and the use of our improved understanding of moral psychology to further refine and develop these methods. (shrink)

The desire-satisfaction theory of well-being says, in its simplest form, that a person’s level of welfare is determined by the extent to which their desires are satisfied. A question faced by anyone attracted to such a view is, *Which desires*? This paper proposes a new answer to this question by characterizing a distinction among desires that isn’t much discussed in the well-being literature. This is the distinction between what a person wants in a merely behavioral sense, in that the person (...) is, for some reason or other, disposed to act so as to try to get it, and what a person wants in a more robust sense, the sense of being *genuinely attracted* to the thing. I try to make this distinction more clear, and I argue for its axiological relevance by putting it to work in solving four problem cases for desire satisfactionism. The theory defended holds that only desires in the latter, genuine-attraction sense are relevant to welfare. (shrink)

In this essay I present an overview of the problem of climate change, with attention to issues of interest to feminists, such as the differential responsibilities of nations and the disproportionate “vulnerabilities” of females, people of color, and the economically disadvantaged in relation to climate change. I agree with others that justice requires governments, corporations, and individuals to take full responsibility for histories of pollution, and for present and future greenhouse gas emissions. Nonetheless I worry that an overemphasis on household (...) and personal-sphere fossil fuel emissions distracts from attention to higher-level corporate and governmental responsibilities for addressing the problem of climate change. I argue that more attention should be placed on the higher-level responsibilities of corporations and governments, and I discuss how individuals might more effectively take responsibility for addressing global climate change, especially when corporations and governments refuse to do so. (shrink)

This paper is an enquiry into the logical, metaphysical, and physical possibility of time travel understood in the sense of the existence of closed worldlines that can be traced out by physical objects. We argue that none of the purported paradoxes rule out time travel either on grounds of logic or metaphysics. More relevantly, modern spacetime theories such as general relativity seem to permit models that feature closed worldlines. We discuss, in the context of Gödel's infamous argument for the ideality (...) of time based on his eponymous spacetime, what this apparent physical possibility of time travel means. Furthermore, we review the recent literature on so-called time machines, i.e., of devices that produce closed worldlines where none would have existed otherwise. Finally, we investigate what the implications of the quantum behaviour of matter for the possibility of time travel might be and explicate in what sense time travel might be possible according to leading contenders for full quantum theories of gravity such as string theory and loop quantum gravity. (shrink)

Can there be phenomenal consciousness without self-consciousness? Strong intuitions and prominent theories of consciousness say “no”: experience requires minimal self-awareness, or “subjectivity”. This “subjectivity principle” faces apparent counterexamples in the form of anomalous mental states claimed to lack self-consciousness entirely, such as “inserted thoughts” in schizophrenia and certain mental states in depersonalization disorder. However, Billon & Kriegel have defended SP by arguing that while some of these mental states may be totally selfless, those states are not phenomenally conscious and thus (...) do not constitute genuine counterexamples to SP. I argue that this defence cannot work in relation to certain experiences of ego dissolution induced by potent fast-acting serotonergic psychedelics. These mental states jointly instantiate the two features whose co-instantiation by a single mental state SP prohibits: phenomenal consciousness and total lack of self-consciousness. One possible objection is that these mental states may lack “me-ness” and “mineness” but cannot lack “for-me-ness”, a special inner awareness of mental states by the self. In response I propose a dilemma. For-me-ness can be defined either as containing a genuinely experiential component or as not. On the first horn, for-me-ness is clearly absent from my counterexamples. On the second horn, for-me-ness has been defined in a way that conflicts with the claims and methods of its proponents, and the claim that phenomenally conscious mental states can totally lack self-consciousness has been conceded. I conclude with some reflections on the intuitive plausibility of SP in light of evidence from altered states. (shrink)

What is the epistemological significance of deep disagreement? Part I explored the nature of deep disagreement, while Part II considers its epistemological significance. It focuses on two core problems: the incommensurability and the rational resolvability problems. We critically survey key responses to these challenges, before raising worries for a variety of responses to them, including skeptical, relativist, and absolutist responses to the incommensurability problem, and to certain steadfast and conciliatory responses to the rational resolvability problem. We then pivot to the (...) ethical and political dimensions of deep disagreement. We focus on whether an unwillingness to engage with positions one considers to be immoral or repugnant might be good, and conclude with some reflections on the moral risks of engagement. (shrink)

Psychedelic ingestion and meditative practice are both ancient methods for altering consciousness that became widely known in Western society in the second half of the 20th century. Do the similarities begin and end there, or do these methods – as many have claimed over the years – share some deeper common elements? In this chapter I take a neurophilosophical approach to this question and argue that there are, indeed, deeper commonalities. Recent empirical studies show that psychedelics and meditation modulate overlapping (...) brain networks involved in the sense of self, salience, and attention; moreover, psychedelics can occasion lasting increases in “mindfulness-related capacities” for taking a non-reactive stance on one’s inner experience (e.g. Sampedro et al. 2017). The self-binding theory of psychedelic ego dissolution (Letheby and Gerrans 2017) offers a plausible explanation of these findings: by disrupting self-related beliefs implemented in high-level cortical networks, both psychedelics and meditation can “unbind” mental contents from one’s self-model, moving these contents along the continuum from phenomenal transparency to opacity (cf. Metzinger 2003). In other words, both psychedelics and meditation can expose and weaken our foundational beliefs about our own identity, allowing us to disidentify with these beliefs and see them as “just thoughts”. There are connections between these ideas and recent arguments suggesting that psychedelic use may have epistemic benefits consistent with philosophical naturalism (Letheby 2015, 2016, 2019). I conclude with a proposal: these connections may help in thinking about the putative epistemic benefits of meditation practice from a naturalistic perspective. (shrink)

This book examines the way in which new discoveries about genetic and neuroscience are influencing our understanding of human behaviour. As scientists unravel more about the ways in which genes and the environment work together to shape the development of our brains, their studies have importance beyond the narrow confines of the laboratory. This emerging knowledge has implications for our notions of morality and criminal responsibility. The extent to which "biological determinism" can be used as an explanation for our behaviour (...) is of interest to philosophers reflecting on the free will versus determinism debate. It also has repercussions for the criminal justice system; in courtrooms around the world, defence lawyers are beginning to appeal to genetic and brain imaging data as grounds for finding their clients not guilty. Can a defendant's genes or the structure of his brain be used as an excuse for his behaviour? Is criminality "hardwired"? Is it legitimate to claim "I couldn't help it, my genes made me do it"? This book appeals to anyone interested in the link between behaviour and genetics, the science and philosophy of moral responsibility and/or criminal law. (shrink)

Any attempt to construct a realist interpretation of quantum theory founders on the Kochen-Specker theorem, which asserts the impossibility of assigning values to quantum quantities in a way that preserves functional relations between them. We construct a new type of valuation which is defined on all operators, and which respects an appropriate version of the functional composition principle. The truth-values assigned to propositions are (i) contextual; and (ii) multi-valued, where the space of contexts and the multi-valued logic for each context (...) come naturally from the topos theory of presheaves. The first step in our theory is to demonstrate that the Kochen-Specker theorem is equivalent to the statement that a certain presheaf defined on the category of self-adjoint operators has no global elements. We then show how the use of ideas drawn from the theory of presheaves leads to the definition of a generalised valuation in quantum theory whose values are sieves of operators. In particular, we show how each quantum state leads to such a generalised valuation. A key ingredient throughout is the idea that, in a situation where no normal truth-value can be given to a proposition asserting that the value of a physical quantity A lies in a set D of real numbers , it is nevertheless possible to ascribe a partial truth-value which is determined by the set of all coarse-grained propositions that assert that some function f(A) lies in f(D), and that are true in a normal sense. The set of all such coarse-grainings forms a sieve on the category of self-adjoint operators, and is hence fundamentally related to the theory of presheave. (shrink)

One recent development in epistemology, the philosophical study of knowledge, is the notion of ‘epistemic innocence’ introduced by Bortolotti and colleagues. This concept expresses the idea that certain suboptimal cognitive processes may nonetheless have epistemic (knowledge-related) benefits. The idea that delusion or confabulation may have psychological benefits is familiar enough. What is novel and interesting is the idea that such conditions may also yield significant and otherwise unavailable epistemic benefits. I apply the notion of epistemic innocence to research on the (...) transformative potential of psychedelic drugs. The popular epithet ‘hallucinogen’ exemplifies a view of these substances as fundamentally epistemically detrimental. I argue that the picture is more complicated and that some psychedelic states can be epistemically innocent. This conclusion is highly relevant to policy debates about psychedelic therapy. Moreover, analysing the case of psychedelics can shed further light on the concept of epistemic innocence itself. (shrink)

Open-minded people should endorse dogmatism because of its explanatory power. Dogmatism holds that, in the absence of defeaters, a seeming that P necessarily provides non-inferential justification for P. I show that dogmatism provides an intuitive explanation of four issues concerning non-inferential justification. It is particularly impressive that dogmatism can explain these issues because prominent epistemologists have argued that it can’t address at least two of them. Prominent epistemologists also object that dogmatism is absurdly permissive because it allows a seeming to (...) provide justification even if the seeming was caused in some apparently inappropriate way. I conclude by disarming this objection. (shrink)

In their recent article “A Hierarchy of Classical and Paraconsistent Logics”, Eduardo Barrio, Federico Pailos and Damien Szmuc present novel and striking results about meta-inferential validity in various three valued logics. In the process, they have thrown open the door to a hitherto unrecognized domain of non-classical logics with surprising intrinsic properties, as well as subtle and interesting relations to various familiar logics, including classical logic. One such result is that, for each natural number n, there is a logic which (...) agrees with classical logic on tautologies, inferences, meta-inferences, meta-meta-inferences, meta-meta-...-meta-inferences, but that disagrees with classical logic on n + 1-meta-inferences. They suggest that this shows that classical logic can only be characterized by defining its valid inferences at all orders. In this article, I invoke some simple symmetric generalizations of BPS’s results to show that the problem is worse than they suggest, since in fact there are logics that agree with classical logic on inferential validity to all orders but still intuitively differ from it. I then discuss the relevance of these results for truth theory and the classification problem. (shrink)

That laws of nature play a vital role in explanation, prediction, and inductive inference is far clearer than the nature of the laws themselves. My hope here is to shed some light on the nature of natural laws by developing and defending the view that they involve genuine relations between properties. Such a position is suggested by Plato, and more recent versions have been sketched by several writers.~ But I am not happy with any of these accounts, not so much (...) because they lack detail or engender minor difficulties, though they do, but because they share a quite fundamental defect. My goal here is to make this defect clear and, more importantly, to present a rather different version of this general conception of laws that avoids it. I begin by considering several features of natural laws and argue that these are best explained by the view that laws involve properties, that this involvement takes the form of a genuine relation between properties, and, finally, that the relation is a metaphysically necessary one. In the second section I start at the other end, and by reflecting on the nature of properties arrive at a similar account of natural laws. In the final section I develop this account in more detail, with emphasis on the nature of the relation between properties it invokes. Along the way several natural objections to the account are answered. (shrink)

Much of my book Philosophy of Psychedelics is devoted to elaborating and defending two basic claims: that psychedelic therapy works mainly by changing mental representations of the self, and that it has many epistemic benefits consistent with a naturalistic worldview. The commentaries in this symposium generally focus on one or the other of these claims. On the mechanistic front, the commentaries by Hoffman and by Martin and Sterzer seek to supplement my account by drawing attention to factors it does not (...) emphasize. In this reply I agree with most of their claims, but propose some important qualifications. Meanwhile, the commentaries by Lyon and Farrenikova and by Colombo challenge some core commitments of my account. I agree with many of their claims, but defend some of these core commitments. On the epistemological front, Bortolotti and Murphy-Hollies endorse the overall shape of my account and make some productive connections to ideas concerning agency-first epistemology and self know-how. Caporuscio brings into play the idea of self-shaping, which connects to self know-how, but argues against certain core claims of my account. I endorse many of these claims about agency-first, self know-how, and self-shaping, but propose some important qualifications. Finally, Fink agrees that psychedelic experiences can have some epistemic benefits, but argues that these do not pertain to epistemic justification, and that the main benefit is increased understanding. I am sympathetic to Fink’s proposal about understanding, but criticize some of his arguments for the thesis of Psychedelic Justification Impossibilism. (shrink)

This paper aims to explain why the laws of nature are held fixed in counterfactual reasoning. I begin by highlighting three salient features of counterfactual reasoning: it is conservative, nomically guided, and it uses hindsight. I then present a rationale for our engagement in counterfactual reasoning that aims to make sense of these features. In particular, I argue that counterfactual reasoning helps us evaluate the evidential relations between unanticipated pieces of evidence and various hypotheses of interest about the history of (...) the actual world. Given this goal, it makes a great deal of sense that counterfactual reasoning would have the aforementioned features. Additionally, it turns out that this account of counterfactual reasoning is nicely congruent with Humean views of laws. Specifically, it can explain, in a Humean-friendly way, both why the laws are counterfactually resilient, and why we may be inclined to have anti-Humean intuitions in the first place, even if some form of Humeanism is correct. (shrink)

The desire-satisfaction theory of welfare says, roughly, that one's life goes well to the extent that one's desires are satisfied. On standard 'actualist' versions of the theory, it doesn't matter what you desire. So long as you are getting what you actually want – whatever it is – things are going well for you. There is widespread agreement that these standard versions are incorrect, because we can desire things that are bad for us -– in other words, because there are (...) 'defective desires'. The aim of this paper is to defend the actualist desire-satisfaction theory against the problem of defective desires. I aim to show how the theory can accommodate the obvious fact that we can desire things that are bad for us. Admittedly, there are kinds of allegedly defective desire the theory cannot accommodate, but these desires, I argue, turn out not to be defective in the relevant way. (shrink)

Many philosophers believe that aesthetic testimony can provide aesthetic knowledge. This leaves us with the question: why does getting aesthetic knowledge by experience – by seeing a painting up close, or witnessing a performance first-hand – nevertheless seem superior to aesthetic testimony? I argue that it is due to differences in their epistemic value; in the diversity of epistemic goods each one provides. Aesthetic experience, or the experience of art or other aesthetic objects, affords multiple, distinctive epistemic goods whereas aesthetic (...) testimony affords less. In particular, it provides aesthetic knowledge of truths, a kind of propositional knowledge, as well as aesthetic knowledge of things, a kind of non-propositional knowledge. Although aesthetic experience is superior because it has more epistemic value, this doesn’t mean that aesthetic testimony provides weaker justification for aesthetic belief than aesthetic experience; the difference is evaluative, not normative. In this way, we can explain a key pessimistic intuition about aesthetic testimony – that it is inferior to aesthetic experience – whilst preserving the optimistic view that aesthetic testimony makes aesthetic knowledge available to others. The superior epistemic value of first-hand aesthetic experience is compatible with a number of important observations about aesthetic testimony, including the importance of aesthetic trust. (shrink)

A "good" arguer is like an architect with a penchant for civil and civic engineering. Such an arguer can design and present their reasons artfully about a variety of topics, as good architects do with a plenitude of structures and in various environments. Failures in this are rarely hidden for long, as poor constructions reveal themselves, often spectacularly, so collaboration among civical engineers can be seen as a virtue. Our logical virtues should be analogous. When our arguments fail due to (...) being uncivil and demagogic, since we inhabit the arguments we build, we are all crushed beneath our flawed reasoning. This mixed metaphor takes us to a self-referential analysis of argumentation, analogy, and humor. I argue that good argumentation strives to collaboratively convince rather than belligerently persuade. A convincing means toward this end is through humorous analogical arguments, whether the matter at hand is ethical, logical, theological, phenomenological, epistemological, metaphysical, political, or about baseball. (shrink)

In this précis I summarise the main ideas of my book Philosophy of Psychedelics. The book discusses philosophical issues arising from the therapeutic use of “classic” psychedelic drugs such as psilocybin and LSD. The book is organised around what I call the Comforting Delusion Objection to psychedelic therapy: the concern that this novel and promising treatment relies essentially on the induction of non-naturalistic metaphysical beliefs, rendering it epistemically objectionable. I begin the précis by summarizing material from chapters two and three (...) of the book, which review evidence for the therapeutic efficacy of psychedelics, and the facts about their clinical use that prompt the Comforting Delusion Objection. I then summarize materials from chapters four and five of the book, which argue that psychedelic therapy works neither by experience-independent processes of neuroplasticity, nor by inducing non-naturalistic metaphysical ideations, but by altering mental representations of the self. Next, I summarise the specific, speculative account of how this might work that is developed in chapters six and seven of the book. This account is based on the predictive processing theory of brain function and the self-binding theory of self-representation. Chapters eight and nine of the book argue, on the basis of this account, that psychedelic therapy can have significant epistemic and spiritual benefits that are compatible with a naturalistic worldview. I summarize this material, and then, finally, the overall conclusions about psychedelic therapy drawn in the tenth and final chapter of the book. (shrink)

It may seem that epistemic and practical rationality weigh reasons differently, because ties in practical rationality tend to generate permissions and ties in epistemic rationality tend to generate a requirement to withhold judgment. I argue that epistemic and practical rationality weigh reasons in the same way, but they have different "default biases". Practical rationality is biased toward every option being permissible whereas epistemic rationality is biased toward withholding judgment's being required.