Ego loss has nothing to do with which drugs you've taken or whether or not you appear catatonic to outsiders. The only thing ego loss affects is your sense of identity. That means that I can carry on conversations, drive a bus, or buy cigarettes while experiencing ego loss, as long as I am not identified with this body's actions.
When you are identified with the universe, your body is a part of that universe, and you simply cannot help what it does. It's all interconnected and you are just observing what is happening in THIS-MOMENT, without changing it.
It just so happens that some drugs are very good at catalyzing this state. Why? Because you have these ideas, this identity, that consists of borders that you call reality. Some drugs change your perception of this reality so much that your sense of identity changes. Drugs that are very, very powerful at changing your perception will be very, very good at helping you change your identity. Like seeing a cube from two angles, I can suddently see the entire cube, the same is true of psychedelics and ego loss. Suddenly, by seeing reality from another angle, I suddenly see all of reality. It just so happens that some of these drugs also create catatonic states of the body, but if you were to experience ego-loss while not under the influence of said drugs, why would you appear catatonic? It is ONLY your sense of identity that has changed. The "I" in "I exist" could be interpreted as "I am the universe, and it-I exists." In other words, YOU are not catatonic, but the body you used to identify with is.
Ego loss doesn't occur gradually, it occurs instantaneously. If you think you are experiencing it, you are not experiencing it. You are NOT thinking during ego-loss, you may experience the passing of thoughts, but YOU are no longer identified with the thoughts, so YOU are not thinking. YOU only experience during this state. YOU may observe what YOU used to think YOU were as still doing things, but that is no longer YOU, so YOU are not doing them.
The catcher is, the only reason you aren't experiencing it right now is that you're trying to experience it. You want to experience? Stop trying. Lose yourself in this moment. If you are trying, you are trying to change this moment, without realizing that you are already in this moment. So you've lost the objective right at the beginning. Don't try to change this moment. But don't try to don't try either, for that also requires you to change this moment, and it requires the existence of the NEXT moment in which you try, so you see, you've lost the objective again! Completely give up on trying to change *anything*, and you'll have it. That includes trying to change your thoughts, trying to change your sense of self, trying to change your body's position, TRYING TO CHANGE YOUR DESIRE TO CHANGE. You simply
must let everything happen. The only reason the stopping of thought of most medititative practices is helpful is because it is another angle to view the world from, and only helps you realize the whole picture. It is NOT necessary, because ego loss is ONLY A CHANGE IN IDENTITY.
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I almost forgot the original question. The drugs that work best for bringing this change about are those that provide radically different angles for viewing. Drugs that "fuck you up" a lot help the most. By "fuck you up" I mean "fuck up your current sense of identity." If you are currently identifying with your body, drugs that fuck up your physiology are best at changing that, though they may not completely destroy your sense of separateness from others. 5-MeO-DMT is an excellent example of this. On non-breakthrough experiences, users report being "the most fucked up I've ever been" but usually "still completely lucid, able to think about what is going on in a rational manner." This is a radical change in angular perception, but unless you breakthrough, you will only experience the angle, you will only experience "I'm so fucked up." Beceause THAT is the angle. Ego loss is no angle, or it is all angles. It is the absence of the angles, because you see from all of them. What does the concept of angle mean when you have no other viewpoints to compare it to?
In short (sorry for rambling

, it just kills me that everyone gets it when its happening, but then they come out of it and explain it away in terms of their old self), ANY change in perception can facilitate this change of self. That could be reading a book, sipping some coffee, smoking some spirit powder, or chewing on some psychoactive molecules. It is only your interpretation that changes, and literally anything can cause you to realize it.