If the Self Can Dissolve, Was It Ever Solid?

Ego dissolution is one of the most commonly reported experiences in psychedelic sessions, and one of the best researched. So it comes to the old philosophical question: What's left afterward?

One of the most commonly reported experiences in psychedelic sessions, including in our own work, is hard to put into words, and the people who try tend to reach for the same phrase: there was suddenly no one left having the experience. No self that was watching, feeling, judging, only the watching, feeling, judging itself, with no one left for it to happen to.

In research this is called ego dissolution, and since 2016 it even has its own validated questionnaire: eight items like "I felt at one with the universe" or "all notions of self and identity dissolved," used to measure the intensity of the experience [1]. Neurologically, it coincides with reduced activity in the so-called default mode network, the network responsible, among other things, for self-referential thinking, the constant quiet commentary on one's own experience that most people mistake for their self [2]. Quiet that commentary, and the self grows quieter too. One of the cleaner correlations in all of psychedelic research, though still not fully understood.

Which leads to a not-so-small observation: if something can dissolve without anything being missing afterward, if ordinary consciousness simply comes back with all its memories, all its character, all its continuity intact, then whatever "dissolved" was apparently never what holds a person together. What that something actually is has been argued over by philosophers for longer than neuroscience has existed.

This isn't a new idea, however much the scene sometimes likes to act as if psilocybin invented it. Hume made the same claim in the eighteenth century, with fewer substances and more reading time: look inward, and you never find a self, only individual perceptions, a bundle that feels connected only because it remembers itself. No core behind it. Buddhism arrives at the same suspicion by a completely different route: anatta, non-self, for over two thousand years. And Derek Parfit, in his characteristically dry analytic style, argued nearly fifty years ago that personal identity over time is a matter of degree rather than a fixed fact, that what really matters is psychological continuity, not some metaphysical self-substance that probably never existed in the first place.

What psilocybin adds isn't a new argument, but an experience that makes an old claim suddenly not just conceivable but felt. You can read Hume's bundle theory for hours and still wake up believing in your self as firmly as ever. After a session in which it was briefly gone, that belief gets harder to hold onto.

Describing this experience as automatically liberating would be one option. Some people come out of it with real relief, others with a fear that lingers for weeks, precisely because something so fundamental wasn't reliably there for a few hours. Anyone who built their self as a wall of protection, for good reasons, rarely experiences its brief absence as a gift.

This difference can even be measured by now. In a study on psilocybin for treatment-resistant depression, the intensity of "oceanic boundlessness," the open, boundless kind of experience, predicted stronger improvement. "Dread of ego dissolution," the fear of that same dissolving, predicted the opposite [3]. How the experience is met seems to matter more than the substance alone. The effect showed most clearly at the first session and less at later doses, so the relationship can't be cleanly isolated yet.

Whether the self feels just as solid afterward as it did before isn't something that can be answered across the board. For a few hours, it wasn't there to defend itself, and there was nothing that needed defending either. Afterward, the self often feels different: less like a fixed fact, more like something still allowed to change. That makes a therapeutic difference. A supposedly fixed fact like "that's just how I am" becomes easier to revise, easier to view from a distance, and in the best case leads to exactly the shift that research links to improvement. Whether anything helpful comes of it seems to depend less on the dose than on the stance one brings to the experience.

Sources

[1] Nour MM, Evans L, Nutt D, Carhart-Harris RL. Ego-Dissolution and Psychedelics: Validation of the Ego-Dissolution Inventory (EDI). Frontiers in Human Neuroscience 2016;10:269.

[2] Carhart-Harris RL, et al. Neural correlates of the LSD experience revealed by multimodal neuroimaging. PNAS 2016;113(17):4853–4858.

[3] Roseman L, Nutt DJ, Carhart-Harris RL. Quality of Acute Psychedelic Experience Predicts Therapeutic Efficacy of Psilocybin for Treatment-Resistant Depression. Frontiers in Pharmacology 2018;8:974.