This commentary (2021) offers a rebuttal to the opinion piece on Moving Past Mysticism in Psychedelic Science by Sanders and Zijlmans and argues against the notion of demystifying psychedelic experiences or dismissing mystical experiences from the scope of empirical inquiry. Given that all experiences are ineffable by the nature of their subjectivity, it is argued that the epistemic gap between subjective and objective viewpoints of consciousness is a question of philosophy and that it is not the role of science to decide whether metaphysical insights related to mystical experiences are compatible with their particular worldview.
In a recent Viewpoint, Sanders and Zijlmans call for the demystification of psychedelic science. However, they ignore the subjective aspect of psychedelic experiences. For the subject, mystical experiences are felt as real and can yield personally meaningful insights. It is a philosophical question whether they are true.
Sanders and Zijlmans recently argued that psychedelic science should be demystified because concepts such as the mystical experience appear to conflict with a naturalistic, empirical approach. They highlighted that instruments like the Mystical Experience Questionnaire (MEQ-30) probe items such as transcendence of space and time, unity, sacredness and ineffability, and warned that such framing may bias participants and therefore pose both methodological and ethical problems—especially for participants who identify as nonspiritual. Jylkkä replies to that Viewpoint by arguing that the subjective aspect of psychedelic experience deserves philosophical as well as scientific attention. Rather than denying or reducing mystical reports to mere neural events, the author proposes treating metaphysical insights arising in psychedelic states as philosophical intuitions that can be evaluated for truth or falsity. To illustrate this reconciliatory stance, Jylkkä discusses how unitary experiences and panpsychist-type intuitions can be given conceptualisations that are compatible with a scientific worldview.
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Papers in Blossom that reference this study
This paper is a philosophical reply and conceptual analysis rather than an empirical study. The author uses argumentation drawn from philosophy of mind and references to prior empirical and historical literature to evaluate the conceptual relationship between mystical reports in psychedelic research and naturalistic science. Key elements of the approach include: analysing the epistemic status of subjective experience (the so-called epistemic gap), examining the characteristic ineffability of mystical states, critiquing the potential bias introduced by instruments such as the MEQ-30, and surveying philosophical frameworks (for example, Kantian limitations on knowledge, monism, and panpsychism) that could accommodate mystical intuitions without abandoning a naturalistic methodology. No new quantitative data, experimental procedures, or formal empirical methods are reported in the extracted text.
Jylkkä advances several interrelated claims. First, subjective experiences—mystical experiences included—are felt as real by subjects and can produce personally meaningful insights; their felt truthfulness (what William James called "noetic quality") should not be reflexively dismissed. Second, there exists an epistemic gap between subjective experience and objective description: knowing all the neurophysiology associated with a state does not convey what the state is like from the first-person perspective, and this gap implies a form of ineffability common to all experience. Third, ineffability and the epistemic gap do not inherently conflict with naturalism. The author points to naturalistic philosophical strategies, including Kantian-style limits on knowledge and monistic formulations of physicalism, that allow for scientific modelling of consciousness without collapsing subjective content into model syntax. Fourth, questionnaires such as the MEQ-30 can bias participant interpretation and thus raise methodological and ethical concerns; Jylkkä concurs with Sanders and Zijlmans that more neutral psychometric instruments are needed. Fifth, some mystical insights—illustrated by the felt sense that "all is one" or metaphors such as being "waves in a sea of consciousness"—can be mapped onto philosophical positions like monism or panpsychism, which can be formulated so as to be compatible with scientific practice. Finally, the author emphasises that whether such metaphysical claims are true is a distinct philosophical question; neuroscientists can model and report the correlates of mystical experiences but should refrain from adjudicating their metaphysical veracity.
The author interprets these arguments to mean that psychedelic science must balance two commitments: methodological naturalism in empirical inquiry, and respect for the subjective, worldview-forming status of psychedelic insights. Jylkkä positions this reply as a corrective to a too-strict demystification that would ignore or erase participants' philosophical intuitions. In relation to earlier literature, the paper situates mystical experiences within long-standing philosophical debates about consciousness and notes historical instances in which altered states informed philosophical proposals (for example, references to William James and Aldous Huxley). Limitations and uncertainties are acknowledged by treating the truth of metaphysical insights as an open philosophical question rather than an empirical conclusion. The extracted text also recognises the methodological problem that current instruments may lead subjects to interpret experiences in particular ways, and therefore it endorses the development of more neutral measures. For practice and future research, the author suggests that investigators should neither reduce participants' worldviews to brain processes nor uncritically accept metaphysical claims; instead, researchers should model experiences scientifically while engaging with the philosophical implications of those experiences. The paper does not present empirical tests of these proposals.
Jylkkä agrees with Sanders and Zijlmans that psychedelic researchers should create more neutral psychometric tools, but cautions against ignoring the subjective and metaphysical dimensions of psychedelic experiences. The concluding position is that such insights should be treated as philosophical intuitions—part of subjects' worldviews and potentially true or false—rather than being fully psychologised or dismissed as supernatural. Determinations about their veracity remain philosophical questions and do not preclude scientific modelling of the experiences themselves.
Sanders and Zijlmans refer to the "ontological shock" related to psychedelic experience, a radical shift in the subject's worldview. The experience may include philosophical and metaphysical insights which are radically new for the subject. For example, William James reported how he understood Hegel's philosophy under the influence of nitrous oxide, and mescaline experience was a catalyst for Aldous Huxley's "reducing valve" theory of consciousness. Reference to philosophical intuitions also play a key role in questionnaires like MEQ-30, represented by items such as "gain of insightful knowledge experienced at an intuitive level", or experience of acquiring knowledge of the "ultimate nature of reality".The psychedelic insights have what William James called "noetic quality" and are felt as true. It would not do justice to them to completely psychologize them or to treat them as merely neural processes. They are not just any kind of neuralpsychological processes, but instead they form the subject's worldview. To compare, also the naturalistic-materialistic worldview can be considered as a psychological process or a brain process, but its adherents consider it as depicting the world as it really is. To illustrate what kinds of philosophical insights psychedelic experience could afford, and how they could be rational and in line with the scientific worldview, I briefly discuss unitary experiences and panpsychist intuitions about the ultimate nature of reality. Psychedelic experience can yield the unitary insight that "all is one". From a philosophical perspective, this may be taken to represent monism, i.e., the claim that everything belongs to one single ontological class. This claim need not conflict with naturalism or physicalism, because even physicalism itself is a monistic theory. It holds that everything, including consciousness, is physical. According to physics, the universe (from unus, the Latin word for one) is a unitary whole, and we are all forms of the same energy that originated in the Big Bang. This is compatible with psychedelic experiences of unity, if they are interpreted as the claim that everything belongs to one fundamental kind that constitutes reality. What if the psychedelic subject claims to have gained insight into the ultimate nature reality? To illustrate, consider that the subject has come to believe that we are "waves in a sea of consciousness". This could be elaborated as the thesis that consciousness is fundamental, or that everything that exists is continuous with consciousness. In philosophy, this is known as panpsychism. It would be ignorant to dismiss insights like this as contradictory with science, as panpsychism can be formulated in a way that is compatible with natural science and materialism.For example, it can be held that experiential properties ground the dispositions and relations that science describes, or that consciousness is part of the concrete reality that science models based on observations. 11 Even if we are skeptical about such theories, we must admit that the compatibility between panpsychism and naturalism is an open philosophical question. Mystical experiences may emphasize our ignorance of reality. It does not conflict with natural science to acknowledge that science is limited to modeling reality or that it cannot tell anything of the reality beyond observations and models. The physicist Stephen Hawking notes that science is "just a set of rules and equations" and continues to ask: "What is it that breathes fire into the equations and makes a universe for them to describe?".This opens room for positive claims about the reality that transcends the scientific observations and models, such as panpsychism.
I agree with Sanders and Zijlmans that psychedelic scientists should develop more neutral psychometric instruments to probe psychedelic experiences. However, we should not ignore the subjective aspects of psychedelic experiences and the metaphysical or even mystical insights associated with them. I have argued that we should not psychologize these intuitions or treat them as mere brain processes, because they constitute the subject's worldview. It is a philosophical question whether they are true or compatible with the scientific worldview.
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