In Philosophy of Psychedelics, Letheby provides a convincing basis for the idea that psychedelics primarily derive their therapeutic potential through mediating favourable changes to self-related belief systems. In this commentary, we take a closer look at the role that contextual factors play in Letheby’s two-factor account of psychedelic therapy. While Letheby acknowledges that psychedelic effects are highly context-dependent, the exact role that context plays in self-modelling during the acute experience is not entirely clear. We argue that context plays an essential (...) role in shaping the ‘discovery’ of alternate self-conceptions during the acute experience. Specifically, users are more likely to experience alterations in self-conception that are consistent with context-dependent features, such as one’s prior mindset and aspects of the external environment. This is consistent with a REBUS model of psychedelic effects, where a corollary effect of relaxing high-level prior beliefs is that the system becomes increasingly sensitised to bottom-up information from lower-level intrinsic sources and the sensory periphery. Furthermore, it may explain why a positive well-intentioned state of mind and a supportive therapeutic environment are more likely to result in positive acute experiences and long-term improvements in mental wellbeing. We see this position as being largely compatible with Letheby’s proposal, but may shift some aspects of its emphasis and framing. In particular, it may conflict with Letheby’s notion that psychedelics lead to a ‘level cognitive playing field’, where self-related hypotheses are thought to be assigned more or less equal probability. (shrink)

According to the predictive coding theory of psychosis, hallucinations and delusions are explained by an overweighing of high-level prior expectations relative to sensory information that leads to false perceptions of meaningful signals. However, it is currently unclear whether the hypothesized overweighing of priors represents a pervasive alteration that extends to the visual modality and takes already effect at early automatic processing stages. Here, we addressed these questions by studying visual perception of socially meaningful stimuli in healthy individuals with varying degrees (...) of psychosis proneness. In a first task, we quantified participants’ prior for detecting faces in visual noise using a Bayesian decision model. In a second task, we measured participants’ prior for detecting direct gaze stimuli that were rendered invisible by continuous flash suppression. We found that the prior for detecting faces in noise correlated with hallucination proneness as well as delusion proneness. The prior for detecting invisible direct gaze was significantly associated with hallucination proneness but not conclusively with delusion proneness. Our results provide evidence for the idea that overly strong high-level priors for automatically detecting socially meaningful stimuli might constitute a processing alteration in psychosis. (shrink)

The aim of this paper is to shed light on and develop what I call a phenomenological conception of experiential justification. According to this phenomenological conception, certain experiences gain their justificatory force from their distinctive phenomenology. Such an approach closely connects epistemology and philosophy of mind and has recently been proposed by several authors, most notably by Elijah Chudnoff, Ole Koksvik, and James Pryor. At the present time, however, there is no work that contrasts these different versions of PCEJ. This (...) paper not only bridges this gap, but also reveals problems in current versions of PCEJ. Consequently, I argue for a new version of PCEJ that focuses on what is given within experience and not on how what is given pushes me towards believing something. (shrink)

The aim of this paper is twofold. The first is an interpretative one as I wish to provide a detailed account of Husserl’s conception of experiential justification. Here Ideas I and Introduction to Logic and Theory of Knowledge: Lectures 1906/07 will be my main resources. My second aim is to demonstrate the currency and relevance of Husserl’s conception. This means two things: Firstly, I will show that in current debates in analytic epistemology there is a movement sharing with Husserl the (...) basic idea that certain experiences gain their justificatory force simply from their distinctive phenomenal character. Secondly, I shall reveal the benefits of Husserl’s specific version of this view. Thus, one of my aims is to show that debates in current analytic epistemology could profit from adopting certain Husserlian elements. More precisely, I will defend Husserl’s claim that perceptual experiences are justifiers due to their self-giving phenomenal character as opposed to the currently popular view that it is the phenomenology of pushiness that makes them justifiers. To put it differently, what matters is what is originally given within experience and not how you feel about what is given. (shrink)

In his influential paper “Grasping the Third Realm,” John Bengson raises the question of how we can non-accidentally grasp abstract facts. What distinguishes successful intuition from hallucinatory intuition? Bengson answers his “non-accidental relation question” by arguing for a constitutive relationship: The intuited object is a literal constituent of the respective intuition. Now, the problem my contribution centers around is that Bengson’s answer cannot be the end of the story. This is because, as Bar Luzon and Preston Werner have recently pointed (...) out, this answer leads to the follow-up question of why certain intuitional experiences are constituted by the facts, but others are not. My objective is to answer this question by specifying precisely what is epistemically defective about intellectual hallucinations. My result is that, in stark contrast to perception, intellectual hallucinations are epistemically defective in the sense that something is overlooked. In successful intuition, by contrast, all relevant possibilities/scenarios are considered/imagined. This has crucial epistemological implications. In particular, I argue that intuitions exhibiting a certain phenomenology cannot fail to successfully grasp abstract facts. I call this the non-accidental correctness thesis, which constitutes the main thesis of this paper. (shrink)

In current debates, many philosophers of science have sympathies for the project of introducing a new approach to the scientific realism debate that forges a middle way between traditional forms of scientific realism and anti-realism. One promising approach is perspectivism. Although different proponents of perspectivism differ in their respective characterizations of perspectivism, the common idea is that scientific knowledge is necessarily partial and incomplete. Perspectivism is a new position in current debates but it does have its forerunners. Figures that are (...) typically mentioned in this context include Dewey, Feyerabend, Leibniz, Kant, Kuhn, and Putnam. Interestingly, to my knowledge, there exists no work that discusses similarities to the phenomenological tradition. This is surprising because here one can find systematically similar ideas and even a very similar terminology. It is startling because early modern physics was noticeably influenced by phenomenological ideas. And it is unfortunate because the analysis of perspectival approaches in the phenomenological tradition can help us to achieve a more nuanced understanding of different forms of perspectivism. The main objective of this paper is to show that in the phenomenological tradition one finds a well-elaborated philosophy of science that shares important similarities with current versions of perspectivism. Engaging with the phenomenological tradition is also of systematic value since it helps us to gain a better understanding of the distinctive claims of perspectivism and to distinguish various grades of perspectivism. (shrink)

Solar radiation management (SRM) may help to reduce the negative outcomes of climate change by minimising or reversing global warming. However, many express the worry that SRM may pose a moral hazard, i.e., that information about SRM may lead to a reduction in climate change mitigation efforts. In this paper, we report a large-scale preregistered, money-incentivised, online experiment with a representative US sample (N = 2284). We compare actual behaviour (donations to climate change charities and clicks on climate change petition (...) links) as well as stated preferences (support for a carbon tax and self-reported intentions to reduce emissions) between participants who receive information about SRM with two control groups (a salience control that includes information about climate change generally and a content control that includes information about a different topic). Behavioural choices are made with an earned real-money endowment, and stated preference responses are incentivised via the Bayesian Truth Serum. We fail to find a significant impact of receiving information about SRM and, based on equivalence tests, we provide evidence in favour of the absence of a meaningfully large effect. Our results thus provide evidence for the claim that there is no detectable moral hazard with respect to SRM. [Open access]. (shrink)

A collection of essays investigating key historical and scientific questions relating to the concept of natural purpose in Kant's philosophy of biology.

Quelle politique peut-on faire quand on est un idiot? Loin d'être saugrenue, c'est bien la question qu'on est conduit à se poser inévitablement en lisant l'oeuvre de Gilles Deleuze. L'"idiot" joue, en effet, un rôle incontournable et essentiel dans la philosophie de Deleuze. Il est le personnage conceptuel qui fait tenir cette philosophie dans sa consistance propre. Il se situe à la charnière de l'image de la pensée que le philosophe invoque et suppose plus ou moins implicitement et de la (...) création de concepts qu'il produit explicitement. Aussi, faire de la philosophie, tout comme agir et penser politiquement, c'est toujours une manière de faire l'idiot. Les conséquences de cette approche sont capitales, du fait des questions posées à la réflexion politique classique centrée sur le Droit et l'Etat, du fait aussi des problématiques qui se voient invalidées dans ce champ. La place qui revient au contrôle et au bio-pouvoir, aux zones d'indétermination et aux espaces lisses, permet de prendre une saine distance vis-à-vis de la politique "majoritaire" et de faire apparaître, comme déjà de vieux clichés, bon nombre de thèmes et de concepts revendiqués par les organisations alternatives, mondialistes et subversives récentes. C'est une tout autre idée de la politique, centrée sur les devenirs, que nous invite à méditer la politique deleuzienne de l'idiot. Elle nous ouvre à d'autres espérances, nouvelles, en lien avec un "peuple absent" qui naîtrait avec chaque devenir. (shrink)

This chapter contains section titled: I The Extended Auction II Working in the Peep Show, Flirting in the Square III Insurance Behind a Veil of Ignorance IV Dworkin's Hybrid Scheme V Four Objections to Dworkin VI Ackerman Generalized VII Not Enough Redistribution? VIII Too Much Redistribution? Acknowledgement.

Animal research suggests that central serotonergic neurons are involved in behavioral suppression, particularly anxiety-related inhibition. The hypothesis linking decreased serotonin transmission to reduced anxiety as the mechanism in the anxiolytic activity of benzodiazepines conflicts with most clinical observations. Serotonin antagonists show no marked capacity to alleviate anxiety. On the other hand, clinical signs of reduced serotonergic transmission (low 5-HIAA levels in the cerebrospinal fluid) are frequently associated with aggressiveness, suicide attempts, and increased anxiety. The target article attempts to reconcile such (...) human and animal findings by investigating whether anxiety reduction or increased impulsivity is more Likely to account for animal behavioral changes associated with decreased serotonergic transmission. The effects of manipulating central serotonin in experimental anxiety paradigms in animals (punishment, extinction, novelty) are reviewed and compared with the effects of antianxiety drugs. Anxiety seems neither necessary nor sufficient to induce control by serotonergic neurons on behavior. Further evidence suggests that behavioral effects of anxiolytics thought to be mediated by decreases in anxiety are not caused by the ability of these drugs to reduce serotonin transmission. Blockade of serotonin transmission, especially at the level of the substantia nigra, results in a shift of behavior toward facilitation of responding. This behavioral shift is particularly marked when there is competition between acting and restraining response tendencies and when obstacles prevent the immediate attainment of an anticipated reward. It is proposed that serotonergic neurons are involved not only in behavioral arousal but also in enabling the organism to arrange or tolerate delay before acting. Decreases in serotonin transmission seem to be associated with the increased performance of behaviors that are usually suppressed, though not necessarily because of the alleviation of anxiety, which might contribute to the suppression. (shrink)

The once-lost introduction to the philosophy of science by Philipp Frank (1884-1966), a leading member of the Vienna circle of philosophers and biographer of Albert Einstein.

The conception of social justice presented and defended in Philippe Van Parijs, "Real Freedom for All" entails, among other implication, the justification of an unconditional basic income. It was the subject of seven critical comments that forms issue 22 and part of 23 of ANALYSE & KRITIK. In this article, Van Parijs offers a comprehensive reply.

An introduction to semantics for the general reader. How things mean, from animal communication to music.

This chapter introduces time travel into the Star Wars lore. Time travel stories in which the past is changed are in danger of being inconsistent or plagued by paradoxes. In famous time travel stories such as Back to the Future, the protagonist travels to the past, changes the past, and then returns to a present quite different from the one they left. In contemporary philosophy of time, there are three main approaches to this question: presentism, eternalism, and the growing block (...) universe. Time travel works by entering a place, the World Between Worlds, that connects different points in time and space. In terms of modern physics, the portals in the World Between Worlds may be understood as traversable wormholes. The nature of time and the possibility of time travel have attracted and captivated humanity for centuries. (shrink)