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Psychedelics and Philosophy

Written by Cyrus Rohani-Shukla 

Psychedelic Epistemology – Chris Letheby

The primary intention behind most psychedelic research is to try to understand whether psychedelics can provide safe and effective therapeutic effects. However, another aspect of psychedelics that is equally important — but less explored — is an understanding of whether we can gain knowledge from their use. 

Many individuals who have used psychedelics have reported knowledge- and insight-related benefits from their experiences. But this raises an overarching question regarding the validity of these insights — are they accurate? Or do psychedelics present false information that simply feels convincing? This question falls within the subfield of philosophy called epistemology, or theory of knowledge.

Epistemology includes the inquiry into what defines ‘knowledge‘, its conditions and the obstacles to learning, as well as conceptual frameworks and analytical tools for concluding. Within epistemology, knowledge is categorised into different types based on particular qualities in what they represent and how they are acquired. This includes metaphysical knowledge — knowledge of a spiritual world or different reality.

Metaphysical knowledge is commonly claimed to be acquired during psychedelic experiences. It refers to the idea of having direct knowledge of the existence of higher spiritual concepts, such as cosmic consciousness or a divine Ground of being. This is the central theme of entheogens, where the psychoactive effects provide spiritual development. However, this “knowledge” is dependent on the reality of these insights. If there truly is an elevated reality, then this would be an epistemic benefit. But if not, then this would effectively be a psychedelic-induced illusion.

Dr. Chris Letheby approaches this concept from a naturalist, or physicalist, perspective, suggesting that there is no other reality, and that this “insight” is not true knowledge. However, even under the assumption that spiritual insights aren’t true knowledge, there can still be epistemic benefits from a psychedelic experience. These knowledge benefits can be distinguished into three categories:

  1. propositional knowledge (“knowledge that”)

  2. ability knowledge (“knowledge how”)

  3. acquaintance knowledge (“knowledge by acquaintance”)

Propositional knowledge, or “knowledge that” refers to knowing explicit facts (eg. the capital of France is Paris). In the context of psychedelic experiences, this type of knowledge can be particularly contentious. While the acquisition of specific facts (eg. Paris-France example) is less commonly associated with psychedelic experiences, propositional knowledge could include psychodynamic insights into previously unconscious beliefs and desires or repressed memories. In this sense, propositional knowledge would be certain “facts” about one’s own mind. However, this assumes that these insights are true, which may not necessarily be the case. False memories, or “placebo insights” are seemingly propositional knowledge that isn’t true. This blindspot is an area for exploration and general awareness in the context of psychedelic-assisted psychotherapy.

Ability knowledge, or “knowledge how” refers to knowing how to do certain things (eg. riding a bike). In the context of psychedelic-assisted psychotherapy, this is typically oriented around how to overcome maladaptive patterns that have risen to awareness. For example, one might learn how to deal with and experience emotions rather than rejecting or repressing them. This aligns with the evidence that psychedelic experiences can lead to increased mindfulness-related capacities and psychological flexibility.

Acquaintance knowledge refers to knowing something in the most direct way possible — similar to how an acquaintance is someone you directly know. This is in contrast to indirect or inferential knowledge, which involves drawing knowledge based on other information. Psychedelic experiences can facilitate the ability to acquaint oneself with previously indirect knowledge. For example, one may have beliefs about the vast potential of the mind, or spiritual awareness indirectly, but is then able to make direct contact with these ideas under the guidance of psychedelics. This is supported by anecdotal evidence of individuals who have found that psychedelic experiences have led them to personally feel a sense of harmony and oneness “with all creatures and things”.

Naturalism and Mysticism in Psychedelic Science – Jussi Jylkkä

One fundamental area of tension within the philosophy of psychedelics lies in the veracity of psychedelic-assisted insights — are they true insights, or negative side effects? For example, while psychedelic-assisted therapy has been effective for easing end-of-life complications, it’s also been suggested that this could simply be a “comforting delusion” for those who are sick or dying. One assumption of psychedelic insights is that mystical insights are incompatible with naturalism — but this may not necessarily be true.

A mystical state is a type of altered state that is a core characteristic of psychedelic experiences. The phenomenology of mystical states dates back to 1961 when Walter Terence Stace defined seven key features of the mystical experience:

  1. United/”all is one”.

  2. Non-spatial and nontemporal.

  3. Has a sense of objectivity or reality (“noetic quality”).

  4. Involves feelings of blessedness and joy.

  5. Meeting something divine or sacred.

  6. Involved paradoxical aspects.

  7. Alleged by the mystics to be ineffable or impossible to capture in words.

The third key feature, “has a sense of objectivity or reality” assumes that these insights about the world (eg. “all is one”) are true. This is important as an insight must be considered to be “true” to be considered a metaphysical insight (eg. a visual hallucination of an elf would not be a metaphysical insight). For example, within the MEQ30 (metaphysical insights in the mystical experience questionnaire), items include:

1.2. Experience of pure being and pure awareness (beyond the world of sense impressions)

            1.5. Experience of unity with ultimate reality

            1.8. Experience of the insight that “all is One”

            1.9. Awareness of the life or loving presence in all things.

These items reflect the core insight that there is a fundamental and unifying nature of reality that is beyond sensory comprehension. In mystical experiences, individuals may meet, see, or become one with this ultimate nature. The representation of this concept is often depicted in metaphors, such as “light”, “mind”, or “God”.

Naturalism is founded on two primary components, ontological and epistemological. The ontological pillar is that “all is physical”, meaning that non-physical entities are not real. The epistemological pillar is that ways of knowing reality should be compatible with science, meaning that conclusions not rooted in scientific methodologies are not true knowledge.

Naturalism becomes limiting when trying to understand the concept of consciousness — a non-physical concept. Jylkkä equivalates this point to philosopher Frank Jackson’s thought experiment, Mary’s Room. In this hypothetical, the situation describes a scientist named Mary who lives in a black-and-white world, but with a deep understanding and access to descriptions of the colour. This raises the question of whether Mary would gain knowledge by stepping into a world where she can perceive colour. Jylkkä’s comparison is “Mary on Acid”, raising the question of whether studying psychedelics represents the same knowledge as experiencing psychedelics.

The limitation of naturalism in understanding consciousness is underlined by the limits of science in studying consciousness. This argument of the limitations of science can be formed from three premises:

  1. Consciousness is physical.

  2. There are facts about consciousness that science cannot convey.

  3. Thus, there are facts about the physical that science cannot convey.

This argument creates a gap in the capabilities of science and an understanding of consciousness, which can be viewed from different perspectives. The first is Russellian Monism, which suggests that consciousness is intrinsic, and science can only model relational properties, not intrinsic properties. The second is naturalistic monism, which is founded on the basis that science is not limited to modeling a specific class of properties, but to modeling simpliciter.

In the context of psychedelic experiences, this can be related to the fundamental, or intrinsic, nature of reality. This refers to the aspects of reality that are beyond observations and theories, in essence, the inaccessible aspects of reality. In psychedelic experiences, it is not uncommon for individuals to meet or become one with this intrinsic nature. This fundamental nature is referenced by the aforementioned metaphors, such as “light”, “mind”, or “God” as it is an ineffable experience. In this way, psychedelics amplify what consciousness is in itself and enables us to see beyond models.

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