While neurophenomenal structuralism (NPS) is typically viewed as an account of why an experience, i.e. a conscious mental state, has a specific phenomenal character, Sascha Fink has suggested that NPS might also account for why one has an experience in the first place. According to Fink, the character-determining structures are incorporated in larger (meta-)structures that make the incorporated...
Two kinds of behavioral dissociation are distinctive of the so-called split-brain phenomenon and first motivated the thought that split-brain consciousness might be structurally dual, with each cerebral hemisphere associated with a distinct stream or sphere of consciousness. One of these behavioral dissociations, however, tends to diminish in observed frequency and severity over time. What...
Methodological structuralism is a research program that seeks to identify neural correlates of consciousness (NCCs) by mapping phenomenal similarity relationships onto the similarity relations between neural population activity. This paper presents a discussion of the potential benefits of methodological structuralism for the neurosciences of consciousness, namely as a specific theory of neural...
Analytical examinations of subjective experience are hampered by the first-person limitation described by Nagel (1974) in “What is it like to be a bat?”. This comment compares two examinations on the nature of subjective experience: Michael Newall’s (2025) analysis of tetrachromatic colour perception and Jordi Galiano-Landeira and Núria Peñuelas’ (2025) exploration of AI phenomenological...
People with fantasy proneness and dispositions towards absorption and hypnotizability encounter waking thoughts that are particularly bizarre or dreamlike in nature. This suggests not only a continuity between dreaming and waking thoughts—what we refer to as continuity of thought—but perhaps stable individual differences in continuity of thought. The personality trait transliminality, which has...
The scientific study of lucid sleep, defined as the ability to retain critical self-awareness during ongoing sleep, has traditionally focused on lucid dreaming and induction techniques that specifically target REM sleep. Recently, interest has grown to include other forms of lucid sleep, such as out-of-body experiences, sleep paralysis, and “witnessing-sleep” episodes described in Indian...
In this paper I argue that in her new book, Why Delusions Matter, Lisa Bortolotti offers us a new way to dispel a major objection to psychedelic-assisted psychotherapy, the Comforting Delusions Objection.
Molyneux’s problem asks whether a person blind from birth, upon gaining sight, could immediately recognize and distinguish objects by sight alone that were previously known only by touch. Historical and contemporary empirical studies have explored this question with inconclusive results due to empirical limitations. More recently, Held and colleagues (2011) found that treated congenitally blind...
I introduce a novel multidimensional framework tailored to investigate a set of phenomena that might appear intractable and render them amenable to scientific inquiry. In particular, I focus on examining altered states of consciousness that appear to the experiencing subject as “contentless” or “objectless” states in some form, either by having disrupted or reduced content of awareness, or...
The intuitive experience of dreaming is that we “see” something with our mind’s eye and react to it. Indeed, dream formation conceptualizations have often focused on the visual image-to-verbal thought direction of causality, inspired by bottom-up models of perception. However, despite being experienced as external to us, the dream environment is internally generated, meaning that dreams are...
Research on the specific features of daydreaming compared with mind-wandering and night dreaming is a neglected topic in the philosophy of mind and the cognitive neuroscience of spontaneous thought. The extant research either conflates daydreaming with mind-wandering (whether understood as task-unrelated thought, unguided attention, or disunified thought), characterizes daydreaming as opposed...
A common view about the phenomenology of episodic remembering has it that when we remember a perceptual experience, we can relive or re-experience many of its features, but not its characteristic presence. In this paper, we challenge this common view. We first say that presence in perception divides into temporal and locative presence, with locative having two sides, an objective and a...
This paper explores the relationship between religious belief and religious experience, bringing out a role for episodic memory that has been overlooked in the epistemology of religion. I do so by considering two questions. The first, the “Psychological Question,” asks what psychological role religious experiences play in causally bringing about religious beliefs. The second, the “Reliability...
In recent years increasing attention has been given to systematic comparison of theories of consciousness. Laudable practical projects have emerged in this regard, such as adversarial collaboration and the development of databases lending themselves to comparisons of empirical support for theories. In addition to the practical advances, theoretical advances have been made, such as a list of...
Smartphone use plays an increasingly important role in our daily lives. Philosophical research that has used first wave or second wave theories of extended cognition in order to understand our engagement with digital technologies has focused on the contribution of these technologies to the completion of specific cognitive tasks (e.g., remembering, reasoning, problem-solving, navigation)....
Integrated information theory (IIT) of consciousness proposes an identity between its causal structure and phenomenology. Through this assertion, IIT aims to explain consciousness by prioritizing first-person experience. However, despite its phenomenology-first stance, developments in IIT have overlooked temporality. As such, we argue that at present IIT’s phenomenological analysis is...
This special issue focuses on the Philosophy of Psychedelics (OUP 2021) by Chris Letheby in the form of a book symposium. Introduced by Matthew Johnson (2022), Letheby presents the main claims of this book that explores the apparent conflict between psychedelic therapy and naturalism in a précis (Letheby, 2022a). Seven contributions criticize, expand or comment on Letheby's arguments,...
Letheby’s naturalistic theory of psychedelic therapy argues that the therapeutic power of psychedelics lies in their ability to allow individuals “to discover the contingency, mutability and simulatory nature of their own sense of identity and habitual modes of attention.” The general shape of this project is persuasive; it is hard to see how the claim that successful therapy must involve...
Chris Letheby argues in Philosophy of Psychedelics that psychedelics and knowledge are compatible. Psychedelics may cause new mental states, some of which can be states of knowledge. But the influence of psychedelics is largely psychological, and not all psychological processes are epistemic. So I want to build on the distinction between processes of discovery and processes of justification to...
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 (‘set’ and ‘setting’) play in Letheby’s two-factor account of psychedelic therapy. While Letheby...
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...
Letheby’s "Philosophy of Psychedelics" relies on Predictive Processing to try and find unifying explanations relevant to understanding how serotonergic psychedelics work in psychiatric therapy, what subjective experiences are associated with their use and whether such experiences are epistemically defective. But if Predictive Processing lacks genuinely explanatory unifying power, Letheby’s...
What makes psychedelic psychotherapy work? Is it the induction of psychedelic experience, with its distinct patterns of hallucinations and insights, or is it the neural ‘shakeup’ that moves the brain out of its regular mode of functioning and into a more disordered state? We consider the role that attention-related phenomenological changes play in psychedelic transformation and psychotherapy....
Letheby’s book is an engaging and crystal-clear exploration of the philosophical issues raised by the use of psychedelic drugs. In this paper, we focus on the epistemological issues Letheby examines in chapter 8 and argue that his analysis requires an agency-first approach to epistemic evaluation. On an agency-first approach, epistemic evaluation is about identifying the skills agents needs to...