•  125
    Psychedelics beyond medicine: Treatment, enhancement, hype, consent, and the limits of medicalization
    with Mina Caraccio, Katherine Cheung, Sebastian Porsdam Mann, Lori Bruce, Edward Jacobs, Daniel Villiger, Julian Sandbrink, Christopher Register, Mette Leonard Høeg, Sean Clancy, Khaleel Rajwani, Emma C. Gordon, Giovanni Spitale, Neil Levy, Keisha Ray, Yuria Celidwen, Ilina Singh, Julian Savulescu, David Bryce Yaden, and Brian D. Earp
    Philosophical Psychology 38 (7): 3340-3383. 2025.
    The current revival of interest in classic psychedelics and other psychoactives such as ketamine and MDMA, coupled with changes to their regulatory status in many jurisdictions, necessitates rigorous ethical guidelines both within and beyond clinical and scientific contexts. This paper examines crucial ethical, philosophical, and policy considerations needed to ensure psychedelic use across various settings remains equitable, beneficial, consensual, and safe, with appropriate accountability mech…Read more
  •  53
    Philosophers have argued that people with psychiatric conditions are vulnerable to epistemic injustice because their testimony is systematically, and unjustly, discredited relative to psychotypical individuals. Whether such differences in credibility amount to epistemic injustice is a normative question, yet whether and how they occur is an empirical one. In five pre-registered experiments (N = 1,908) on Prolific, we tested whether and when people grant less credibility to psychiatric patients’ …Read more
  •  303
    Background: Contemporary societies are rife with moral disagreement, resulting in recalcitrant disputes on matters of public policy. In the context of ongoing bioethical controversies, are uncompromising attitudes rooted in beliefs about the nature of moral truth? Methods: To answer this question, we conducted both exploratory and confirmatory studies, with both a convenience and a nationally representative sample (total N = 1501), investigating the link between people’s beliefs about moral trut…Read more
  •  209
    The question of what makes someone the same person through time and change has long been a preoccupation of philosophers. In recent years, the question of what makes ordinary or lay people judge that someone is—or isn’t—the same person has caught the interest of experimental psychologists. These latter, empirically oriented researchers have sought to understand the cognitive processes and eliciting factors that shape ordinary people’s judgments about personal identity and the self. Still more re…Read more
  •  9
    Experimental Jurisprudence
    Stanford Encyclopedia of Philosophy. forthcoming.
  •  64
    Background Toomey et al (2024) found that US participants were more likely to follow a medical treatment preference—expressed after substantial cognitive decline—of a third person rather than their own future self. This correlated with a greater tendency to see the third person as still their true self. We hypothesised that the greater epistemic access one has to one’s own true self as opposed to others might drive this difference. Methods A codebook designed to capture different kinds of eviden…Read more
  •  880
    The True Self and Decision-Making Capacity
    American Journal of Bioethics 24 (8): 86-88. 2024.
    Jennifer Hawkins (2024) offers two cases that challenge traditional accounts of decision-making capacity, according to which respect for a medical decision turns on an individual’s cognitive capacities at the time the decision is made (Hawkins 2024; Appelbaum and Grisso 1988). In each of her described cases (involving anorexia nervosa and grief, respectively), a patient makes a decision that—although instrumentally rational at the time—does not reflect the patient’s longer-term values due to bei…Read more
  •  140
    Background Advance healthcare decision-making presumes that a prior treatment preference expressed with sufficient mental capacity (“T1 preference”) should trump a contrary preference expressed after significant cognitive decline (“T2 preference”). This assumption is much debated in normative bioethics, but little is known about lay judgments in this domain. This study investigated participants’ judgments about which preference should be followed, and whether these judgments differed depending o…Read more
  •  1337
    Experimental Philosophical Bioethics and Normative Inference
    Theoretical Medicine and Bioethics 42 (3-4): 91-111. 2021.
    This paper explores an emerging sub-field of both empirical bioethics and experimental philosophy, which has been called “experimental philosophical bioethics” (bioxphi). As an empirical discipline, bioxphi adopts the methods of experimental moral psychology and cognitive science; it does so to make sense of the eliciting factors and underlying cognitive processes that shape people’s moral judgments, particularly about real-world matters of bioethical concern. Yet, as a normative discipline situ…Read more
  •  491
    Responding to recent concerns about the reliability of the published literature in psychology and other disciplines, we formed the X-Phi Replicability Project to estimate the reproducibility of experimental philosophy. Drawing on a representative sample of 40 x-phi studies published between 2003 and 2015, we enlisted 20 research teams across 8 countries to conduct a high-quality replication of each study in order to compare the results to the original published findings. We found that x-phi stud…Read more
  •  116
    The Brain Death Criterion in Light of Value-Based Disagreement Versus Biomedical Uncertainty
    with Gonzalo Díaz-Cobacho and Daniel Martin
    American Journal of Bioethics 24 (1): 123-126. 2024.
    Since the introduction of a new criterion for determining death (i.e., the brain death criterion) in 1968, the research community has been embroiled in debates about whether this criterion should b...
  •  145
    There is little debate regarding the acceptability of providing medical care to restore physical or mental health that has deteriorated below what is considered typical due to disease or disorder (i.e., providing “treatment”—for example, administering psychostimulant medication to sustain attention in the case of attention deficit disorder). When asked whether a healthy individual may undergo the same intervention for the purpose of enhancing their capacities (i.e., “enhancement”—for example, us…Read more
  •  49
    Healthcare systems often delegate surgical consent-seeking to members of the treating team other than the surgeon (e.g., junior doctors in the UK and Australia). Yet, little is known about public attitudes toward this practice compared to emerging AI-supported options. This first large-scale empirical study examines how laypeople evaluate the validity and liability risks of using an AI-supported surgical consent system (Consent-GPT). We randomly assigned 376 UK participants (demographically repr…Read more
  •  50
    Recent years have seen recurring episodes of tension between proponents of freedom of speech and advocates of the disenfranchised. Recent survey research attests to the ideological division in attitudes toward free speech, whereby conservatives report greater support for free speech than progressives do. Intrigued by the question of whether “canceling” is indeed a uniquely progressive tendency, we conducted a vignette-based experiment examining judgments of offensiveness among progressives and c…Read more
  •  74
    Many bioliberals endorse broadly consequentialist frameworks in normative ethics, implying that a progressive stance on matters of bioethical controversy could stem from outcome-based reasoning. This raises an intriguing empirical prediction: encouraging outcome-based reflection could yield a shift toward bioliberal views among nonexperts as well. To evaluate this hypothesis, we identified empirical premises that underlie moral disagreements on seven divisive issues (e.g., vaccines, abortion, or…Read more
  •  822
    Self-Deception: A Case Study in Folk Conceptual Structure
    Review of Philosophy and Psychology 16 (2). 2025.
    Theoretical debates around the concept of self-deception revolve around identifying the conditions for a behavior to qualify as self-deception. Experiments 1 and 2 revealed that various candidate features—such as intent, belief change, and motive—are treated as sufficient, but non-necessary, conditions according to the lay concept of self-deception. This led us to ask whether there are multiple lay concepts, such that different participants endorse competing theories (the disagreement view), or …Read more
  •  155
    In a recent study, Lantian and colleagues (2024) measured public attitudes toward the use of ‘love drugs’ as introduced through the work of Earp, Savulescu, and their collaborators. Use of a “revol...
  •  83
    The psychedelic psilocybin has shown promise both as treatment for psychiatric conditions and as a means of improving well-being in healthy individuals. In some jurisdictions (e.g., Oregon, USA), psilocybin use for both purposes is or will soon be allowed and yet, public attitudes toward this shift are understudied. We asked a nationally representative sample of 795 US Americans to evaluate the moral status of psilocybin use in an appropriately licensed setting for either treatment of a psychiat…Read more
  •  7
    Conservatives and liberals disagree sharply on matters of morality and public policy. We propose a novel account of the psychological basis of these differences. Specifically, we find that conservatives tend to emphasize the intrinsic value of actions during moral judgment, in part by mentally simulating themselves performing those actions, while liberals instead emphasize the value of the expected outcomes of the action. We then demonstrate that a structural emphasis on actions is linked to the…Read more
  •  1307
    At the height of the Covid-19 pandemic, frontline medical professionals at intensive care units around the world faced gruesome decisions about how to ration life-saving medical resources. These events provided a unique lens through which to understand how the public reasons about real-world dilemmas involving trade-offs between human lives. In three studies (total N = 2298), we examined people’s moral attitudes toward triage of acute coronavirus patients, and found elevated support for utilitar…Read more
  •  79
    Coordination Favors Legal Textualism by Suppressing Moral Valuation
    with Kevin P. Tobia, Guilherme da F. C. F. Almeida, Noel Struchiner, Markus Kneer, Piotr Bystranowski, Vilius Dranseika, Niek Strohmaier, Samantha Bensinger, Kristina Dolinina, Bartosz Janik, Egle Lauraityte, Michael Laakasuo, Alice Liefgreen, Ivars Neiders, Maciej Próchnicki, Alejandro Rosas Martinez, Jukka Sundvall, and Tomasz Żuradzki
  •  36
    Moral psychological exploration of the asymmetry effect in AI-assisted euthanasia decisions
    with Michael Laakasuo, Anton Kunnari, Kathryn Francis, Michaela Jirout Košová, Robin Kopecký, Paolo Buttazzoni, Mika Koverola, Jussi Palomäki, and Marianna Drosinou
    Cognition 262 (C): 106177. 2025.
  •  105
    Apply the Laws, if They are Good: Moral Evaluations Linearly Predict Whether Judges Should Enforce the Law
    with Neele Engelmann, Guilherme da Franca Couto Fernandes de Almeida, Felipe Oliveira de Sousa, Karolina Prochownik, Noel Struchiner, and Stefan Magen
    Cognitive Science 48 (10). 2024.
    What should judges do when faced with immoral laws? Should they apply them without exception, since “the law is the law?” Or can exceptions be made for grossly immoral laws, such as historically, Nazi law? Surveying laypeople (N = 167) and people with some legal training (N = 141) on these matters, we find a surprisingly strong, monotonic relationship between people's subjective moral evaluation of laws and their judgments that these laws should be applied in concrete cases. This tendency is mos…Read more
  •  130
    New Findings on Unconsented Intimate Exams Suggest Racial Bias and Gender Parity
    with Lori Bruce and Brian D. Earp
    Hastings Center Report 52 (2): 7-9. 2022.
    Testimony from hundreds of medical students and numerous physicians and scholars suggests that unconsented intimate exams (UIEs) are unlikely to be rare, isolated incidents. However, much is unknown about the frequency of these exams and the circumstances in which they take place. The Community Bioethics Forum, founded and chaired by one of the authors of this commentary, is a consultative group of diverse community members who provide insights on law and policy to policy‐makers and medical asso…Read more
  •  119
    Historically, empirical research in bioethics has drawn on methods developed within the social sciences, including qualitative interviews, focus groups, ethnographic studies, and opinion surveys, t...
  •  128
    Coordination and expertise foster legal textualism
    with Kevin P. Tobia, Guilherme da F. C. F. de Almeida, N. Struchiner, Markus Kneer, P. Bystranowski, V. Dranseika, N. Strohmaier, S. Bensinger, K. Dolinina, B. Janik, Egle Lauraityte, M. Laakasuo, A. Liefgreen, I. Neiders, M. Prochnicki, A. Rosas, J. Sundvall, and Tomasz Zuradzki
    Proceedings of the National Academy of Sciences of the United States of America 119 (44). 2022.
    A cross-cultural survey experiment revealed a dominant tendency to rely on a rule’s letter over its spirit when deciding which behaviors violate the rule. This tendency varied markedly across (k = 15) countries, owing to variation in the impact of moral appraisals on judgments of rule violation. Compared with laypeople, legal experts were more inclined to disregard their moral evaluations of the acts altogether and consequently exhibited stronger textualist tendencies. Finally, we evaluated a pl…Read more
  •  874
    Governance quality indicators for organ procurement policies
    with David Rodríguez-Arias, Alberto Molina-Pérez, Janet Delgado, Benjamin Söchtig, Sabine Wöhlke, and Silke Schicktanz
    PLoS ONE 16 (6). 2021.
    Background Consent policies for post-mortem organ procurement (OP) vary throughout Europe, and yet no studies have empirically evaluated the ethical implications of contrasting consent models. To fill this gap, we introduce a novel indicator of governance quality based on the ideal of informed support, and examine national differences on this measure through a quantitative survey of OP policy informedness and preferences in seven European countries. Methods Between 2017–2019, we conducted a conv…Read more