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Discussing and Describing psychedelic experiences and effects


I just finished the first week of a class on psychedelics that I am teaching. I enjoyed it so much that I want to highlight some of the main ideas, sprinkling some new ideas along the way.

Discussion on Aidan Lyon's Views on the concept of "psychedelic experience."

The first thing we looked at is the concept of “psychedelic experience.” Here, we turned to Aidan Lyon’s talk, which you can find here. Lyon has a book coming out in October 2023. One of the contentions of the book is that psychedelic experiences can be achieved by other means, i.e., meditation. But the main point here is Lyon’s analysis of “psychedelics.” There are at least three meanings associated with the term.

  1. A trippy experience.

  2. A chemical or compound or drug.

  3. A mind revealing experience.

Most of us are familiar with the first and second definition. However, Lyon points out that, historically, the third option was intended. In other words, researchers studying psychedelics proposed to understand associated experiences as “mind revealing.” Roughly put, the idea is that psychedelic experiences provide information or insights about the mind. One thing that was not clarified in the talk (maybe it's addressed in the book) is the question, "for who is the experience revealing?" Is it revealing only for the individual or is it also revealing to others? That is, if it provides information about the mind to others, then this suggests that psychedelic perspectives can provide data for scientific theories of the mind. That would be a very interesting claim!

Lyon correctly points out that just because the original authors thought psychedelics were mind revealing does not make it true. We need to research whether or to what extent psychedelic experience is mind revealing (and his book intends to assess this).

One thing I am now thinking is that psychedelic experiences may also be “mind-constructing.” Mind revealing says that we get information about the mind from the experience. Mind-constructing says that new aspects of the mind are formed. Consider the common experience of meeting someone while you are drunk. The person may seem a lot less funny and interesting the next day when you are sober. On psychedelics, this is less common. The next day, the person will still have a glow to them that you wouldn’t have appreciated before. One way to interpret this is that the psychedelic experience constructed a framing or way of valuing a person. Finally, we should be careful to avoid either-or dichotomies. Psychedelic experiences can be all the above: trippy, revelatory, constructive.

Okay, I also want to point out an implication of Lyon’s understanding of “psychedelic experience” as mind revealing. About a year ago I made a friend at a conference. He had married, had children, and lovingly supported his spouse through grad school. Then he came out. This was altogether an extremely difficult situation that resulted in significant growth for him. He then told me that one day he came to the sudden realization that had he loved himself, he never would have married. The idea is that he had various notions of what he should be doing, how he would be worthy of love only if he lived in such and such way, and that these guided him to get into a situation that did not fundamentally agree with his preferences. My point in this story is that this is very clearly a mind revealing experience. And it is an experience that does not stem from psychedelic drug usage. What I am getting at is that on Lyon’s definition, psychedelic experiences are not different in kind from all kinds of experience. I don’t mean this as a critique, but it is worth pointing out because some may want to avoid this implication. Some may want a definition of psychedelic experience that makes it distinctive from other kinds of experience. Personally, I don’t debate definitions. I prefer to lay out the definitions clearly, and we decide from there how we will define our terms.

Next, Lyon provides us four dimensions of psychedelic experiences. Scope may be understood as how much is revealed. Using the metaphor of a window, we can say scope refers to the size of the window. Clarity refers to how clear the experience is. Are we able to see out the window or is it dirty? Novelty, then, refers to the newness or the surprise of the information. Is the same old grass and car seen out the window, or is maybe something new there? Duration refers to the length of time an experience lasts. This can be analogous to looking out the window for a long time.

Another fascinating part of Lyon’s talk is a representation of two of the dimensions. These dimensions help us talk about “psychedelic space,” not in a trippy way but rather in a (semi) mathematical way. He represents clarity on the Y-axis and novelty on the X-axis. For example, a meditative practice may represent a high increase of clarity on the X-axis, but it may not present much novelty since it at most provides information that is already there (or at least this is how I interpret Lyon). On the other hand, a high degree of novelty, as trippy experiences usually are, may not have much clarity. Lyon suggests that an experience that combines high degrees of both would take one into psychedelic space; that is, it would be “mind revealing.”

psychedelic experience, meditation, mindfulness, aidon Lyon
screenshot from Lyon's talk

He uses this to make an interesting point about mindfulness. We might understand mindfulness as non-judgemental, accepting awareness of one’s thoughts, emotions, and so forth. Research shows that psychedelics increase mindfulness. Moreover, mindfulness deepens psychedelic sessions. Lyon’s dimensions make sense of this. On his view, psychedelics may work to get one started higher up on psychedelic space. That is, psychedelic experiences increase clarity and novelty. As we increase in these, we increase in self awareness, and this is in part mindfulness.

psychedelic experience, meditation, mindfulness, aidon Lyon
Screenshot from Lyon's talk

Discussion on Chris Letheby's chapter on psychedelic experience

Will Smith recently slapped Chris Rock and many people disagree with him for that. But before that, I went through his entire audiobook: over 16 hours. I was ready to impress everyone with pop culture knowledge and insight. The book is written with help by Mark Manson, who is very good at writing and has a knack for self help that is not full of BS. But now I cannot share my learning because of Will's public relations issue. I am going to do it anyway.

In his book, he talks about the early origins of his acting career. His father struggled to be kind: he would beat Will Smith and his mom. As a result, Will coped by learning to deeply read people. He had to be tuned to the slightest behavioral cue in order to avoid injuries at home. I was also shocked to learn that movie stars work hard–at least Will Smith did. I always assumed that they just act for a while and party in Hollywood for the rest of the time. The book also discusses how a driving factor behind his success was uncle fluffy. Uncle Fluffy is that aspect of Will Smith (named by his therapist) that is a people pleaser. Will worked hard and strived for huge success because he felt he needed the approval of others. I am writing all of this to contextualize his psychedelic experience on ayahuasca in Peru. After taking the drink, he reported floating through space and in an absolutely beautiful feeling. He asks an invisible presence where he was–this place is beautiful. The “goddess” laughs and says “what do you mean silly, this is you.” The experience showed Will Smith that he was so beautiful and thus worthy of love that he did not need all the things he had been struggling for.

Will Smith’s story represents a psychedelic experience. In the rest of this blog, I want to go over a chapter on Chris Letheby’s book on psychedelic experiences in therapy [Chapter 3: The Phenomenology of Psychedelic Therapy]. The aim of his book is to show that, contrary to how things appear, psychedelic experiences in therapy need not be so spooky or metaphysical as Will Smith’s experience suggests. But that is not the point here. I just want to use his chapters to get a better idea of what psychedelic experience is like; I want to better grasp concepts to understand psychedelic experience. We can focus on evaluating those experiences some other time. For now, let's try to describe them.

There’s at least three challenges in trying to describe and understand psychedelic experiences. First, experiences are variable. What one person goes through may be quite different from what another person goes through. Second, experiences have a level of ineffability. It is hard to know what it is like to lose a sense of self without actually losing a sense of self. Lastly, and relatedly, the best way to know what an experience is like is to experience it–not talk about it. I am not about to pass around drugs. I don’t have a solution to these problems, but I do want to acknowledge them. What I will do now is summarize some of the themes and patterns in psychedelic experience, as discussed by Chris Letheby.

The chapter in question is titled The Phenomenology of Psychedelic Therapy. Letheby’s book is focused on showing a more naturalistic understanding of psychedelic therapy, so he focuses here on the experiences of psychedelic therapy. He leaves out some experiences that may not fit in with therapeutic effects, and he doesn’t try to cover all kinds of experiences. So the data we are drawing on is only a sample, but I think it's enough to work with–enough to start understanding psychedelic experiences.

Letheby introduces us to three ways to frame psychedelic experiences: intensification, alteration, novelty. First, intensification is akin to a change in degree on some level. For example, Huxley wrote that mescalin, “...raises all colors to a higher power and makes the percipient aware of innumerable fine shades of difference, to which, at ordinary times, he is completely blind” (40). Others have reported being acutely aware of music: “...The various pieces of music were wonderful... I could hear tiny variations and subtle changes and shadings in the voices and instruments…” (43). Music and dance and ritual has been used in Latin America along with psychedelics such as ayahuasca. Recently, scientists have been studying a therapy method where the patient listens to music in a relaxing environment. These experiences can become very interesting, as the above cited person reported, “There was the sense of the composer touching the divine and channeling its perfection down to the human level…” (43).

Second, alteration is understood as a significant change to something present. An example of alteration is reports of people experiencing walls breathing or pulsing. Another example involves seeing a bit more than is actually there. Someone may vividly see a face inside a cloud. I find that many people can relate to this by remembering childhood experiences. As children, we tend to see a things that adults do not. Another interesting form of alteration is the feeling that time goes by slower. One person reported feeling like they were smoking for three hours when it had only been a minute. Another person saw the world slow down to the extent that it looked like a snapshot.

Another type of common alteration is when people see their therapist or ritual leader as an archetype, such as a Jesus or spiritual leader. One musician I met had an ayahuasca experience in Oregon. He reports the ritual leader acting like a sort of superhero fighting all his problems in forms of demons. It is interesting to me that this happens because he had no previous attachments to the leader he had just met. If it was a sort of father figure, I can imagine one seeing them differently, but this was someone he did not previously know. One interpretation may be that while he did not know the ritual leader, he does have a set of social-cultural expectations of spiritual leaders.

Third, novelty may be considered as something completely new. Here we can bring to mind what most of us think about when we hear about psychedelics. These are the hallucinations. Unusual spiritual and metaphysical scenes. Out of this world colors and scenes. One person reported seeing the branches of the trees as gigantic arms. I’ve heard of others being aware of the tree breathing. Another person rode on pegasus and flew through millions of galaxies. Yet another person knew they would open the curtain and see God. Upon opening the curtain, the person saw his children. This was a sort of revelation about the beauty of his children, which by the sounds of it positively changed his relationship with them. Letheby points out here that focusing on the “hallucination” part of this experience misses an important, parabolic point. The person is changing their values (or coming to realize certain values). So the psychedelic effects involve the interesting experiences, but the effects go beyond that into what is reported as insights or learning.

Having gone through those terms (intensification, alteration, novelty), let me make a few remarks. Letheby is a bit unclear as to how he intends to use these three terms. He says they apply to psychedelic effects on visual perception, but in the rest of the chapter he applies these terms to other kinds of psychedelic effects. For example, he thinks ego dissolution is a sort of alteration to the sense of self. There are at least three other questions worth mentioning here. First, does Letheby think these three terms can be used to describe all or most kinds of psychedelic experiences? Second, how do these terms relate to each other? We might think of intensification as a kind of alteration. To make a color more vivid is to alter it in some way. Alternatively, we might think of alteration as a kind of novelty. To change the vividness of an experience is to make it novel in a sense. Third, we might ask how these concepts apply to psychedelic effects such as those of insight and healing. For instance, in a discussion that we will see below, Letheby notes that a change in self perception led some struggling with addiction to detach from their self understanding as “an alcoholic.” I think these are deep and interesting questions. But we should next talk a bit about other experiences.

Interestingly, Letheby writes that it is less common to get distortions at the level of touch, taste, and smell. Why might this be? One idea is that sight is the main way by which we navigate the world. I think in addition to this is that touch, taste, and smell are less tied to thinking. We not only navigate the world but also think about the world in terms of visual concepts. Time, for example, is thought about as a line or rotating clock--or changing scenes in the world such as time lapse photography shows. My idea suggests that someone predominant in thinking via other senses would have greater distortions in those areas than someone not so predominant in those senses. For example, many blind people have to move about by touching their environment. Maybe blind people would have more tactile hallucinations.

A much discussed psychedelic experience is that of ego dissolution. We might understand ego dissolution as an alteration to the sense of the self. One person reports that the boundaries of their being dissolved. Another identified being one with a flower. More generally, people come to identify with things and the world around them. We can distinguish a few senses of the sense of self, which Letheby borrows from Girn and Christoff’s article.

  • Sense of Control. When I open the door, I have the feeling that it was me who opened the door.

  • Sense of ownership of one’s body and thoughts. When I think, I have the feeling that this is my thought. Many people have reported the experience of getting word from God. A skeptic could interpret this as having thoughts but that form some reason they did not come with the sense of ownership–these were not my thoughts. And from here one may think it is God speaking.

  • Sense of self location. We can all point to where we are in space, but that shouldn’t be taken for granted. We can lose grip on our location.

  • Sense of bodily boundaries. There is an interesting experiment where they ticke a fake hand and they make people feel like it was their hand tickled. Also, phantom limb is a situation where people who have lost a limb still feel itches in that area.

Above I wrote, in passing, that we can distinguish between psychedelic experiences and psychedelic effects. The psychedelic experiences involve what one feels, but psychedelic effects also include what occurs to oneself (e.g., healing) or what one thinks. We may call these kinds of psychological insights improved understanding of oneself, values, relationships, and so forth. One illustration is that psychedelics change the way you see people and relationships. It is not like alcohol where the next day you reject what you thought and felt about someone. In a previous example, we saw the person who pulled curtains expecting to see God but saw his children. But the scenarios don’t have to be that drastic. One may just come to see another person with a certain sort of glow.

Another common scenario involves a re-orientation in values. One person realized they should focus less on material success and more on emotions. They came to see an intense striving for success as pointless. A question to raise here is whether these re-orientation in values are mind revealing, as Lyon proposes, or more mind constructing, as I asked earlier. Do psychedelics make us see values that were "in us" all along, or do we come to have new values? Probably both are true.

I am very excited to see what science discovers about the benefits of ego dissolution (though buddhists may not see it as a new discovery). Already there are various studies that link ego-dissolution to improvements in addiction and depression. For example, one smoker felt that they lost their self understanding as “non-smoker.” A similar experience occurred with someone who had a drinking problem. Apparently, ego dissolution can separate the current self from a past self that is associated with problematic substance abuse. A tangential point worth mentioning is that these experiences are often described as “re-birth,” and this reminds me of born-again Christianity. Born again Christians emphasize the experience of being dead to the world and renewed or reborn in Christ. It is fascinating that these experiences can be had without psychedelic substances.

Lastly, I should say a bit about connectedness and acceptance. People often experience greater connection and acceptance after the psychedelic experience is over. One person started a habit of sitting outside and noticing nature, appreciating it in new ways. This occurs with respect to others as well. And people come to accept features of others, their bodies, their past, and so forth. Obviously, this can have important therapeutic benefits.

Finally, I want to add one speculation before closing. Religion, meditation, and psychedelics all produce very similar experiences. I have not covered this point in this blog, but it is true. I refer the interested reader to the chapter from Letheby for a bit of discussion and some references. Lyon also agrees and argues that psychedelics and meditation can achieve similar experiences. These involve clarity, insight, ego dissolution, and many others. What about religion? I think anyone who has read the bible, believer or not, can agree that many parts of it look like they are produced by psychedelics. To be clear, I know of no evidence that the bible was written by people who were hallucinating. I don’t defend that view; I suspect it is false. I am just saying that what is reported often looks like that. In the bible, snakes talk, monsters attack the world in apocalyptic events, stairs descend from heaven, angels carry messages, and so forth.

What I am saying first is that religion, meditation, and psychedelics all achieve similar experiences. Second, we can ask why this is so? Part of my speculation is that we need a set of overlapping theories explaining all of this. Here is one such theory: all these practices in fact put you in contact with an otherworldly realm. Not everyone will believe this theory. I don't believe it. But it is a theory that connects all the experiences. I think we need a more naturalistic theory.

For example, we may look for a theory according to which the sense of self is partly socially constructed. Why do soldiers march? What is the value? I’ve heard of stories where soldiers made to march for long times begin begin to identify with the group, in an ego-dissolution kind of way. There is something about the rhythms and coordination with others that changes the sense of self. Here is evidence that the sense of self is sensitive to others. A student in my class made an interesting point. A baby is taught that it should follow an eating schedule. So, the idea is that the infant is born into a set of responsibilities. The responsibilities come prior to the self. Mom says you have to eat your cheerios before playing, and the child begins to develop the idea, “I am a cheerio eater; I have obligations to cheerios.” An extended series of experiences like this may be crucial to the development of the sense of self. My speculation is that if the sense of self is partly dependent on social worlds, then we may begin to understand how non-psychedelic practices such as religious communities can produce experiences similar to those of psychedelics, and this is what I mean by a naturalistic set of overlapping theories connecting the domains of religion, meditation, and psychedelics.

In conclusion and to summarize, we began with a discussion on Aidon Lyon’s talk. Lyon proposes to think of psychedelic experiences as “mind revealing.” Mind revealing involves the dimensions of scope, clarity, novelty, and duration. We then turned to Letheby’s discussion on psychedelic experience reports. Letheby used the concepts of intensification, alteration, and novelty to describe the experiences, but also noted that regardless of what occurs in experience, we should also note other effects. The effects involve therapeutic outcomes and psychological insights or re-orientations in values. We have now an important set of philosophical questions that we cannot address here. Namely, how to critically access and construct the concepts we have been given. For example, how do these concepts map onto each other. Maybe intensification is a kind of alteration, or maybe alteration is a kind of novelty. Maybe Letheby's "psychological insight" is a kind of Lyon's "mind revealing experience," which means psychological insight should reduce to the dimensions of scope, clarity, and so forth. I think this is an area of ongoing research in the philosophy of psychedelics. Since the field is new, the central concepts aren’t yet settled.


Letheby C. (2021). Philosophy of psychedelics. Oxford University Press.

Lyon, Aidan. (2023). Psychedelic Experience: Revealing the Mind. Oxford University Press.

In this blog, I discuss his talk here.

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