They discussed this too. One said that sleep paralysis involves lucidity and should therefore be higher up than dreaming, others said that sleep paralysis and lucid dreaming shouldn’t be on opposite sides of dreaming or should be closer together because each can cause each other. Others discussed how different drugs are more or less similar to others or are ‘higher’ and ‘lower’.
It would be fantastic to have such a map and be able to use it, but we don’t. That’s why my diagram just had arrows for the three axes. It was drawn by my son Jolyon Troscianko who has illustrated many of my books, and it was deliberately vague. So will we ever have such a map?
Many people have tried to make them, as I outlined in my textbook on consciousness. For example, psychologist Charles Tart mapped dreaming and other states using as axes ‘ability to hallucinate’ and ‘rationality’; neurologist Steven Laureys used ‘level of consciousness’ and ‘content of consciousness’; and sleep expert, J. Allan Hobson developed a 3D ‘AIM model’ with the dimensions being ‘activation’, ‘input-output gating’ and ‘modulation’. All these were based on scientific research. For example Hobson’s is based on based on the effects of different neurotransmitters. But there are plenty more based on shamanic states, spiritual doctrines, meditation methods or various theories of consciousness.
This conversation is great fun, and after meandering around wild speculations ends up with the truth. The axes are purely imaginary. I had no specific dimensions in mind when I asked Jolyon to draw it and to put arrows for the imagined axes. The drawing is just meant to illustrate the idea that there might be a vast multi-dimensional space of states of consciousness – with some being close to each other and others far apart. One day someone will create a real map. For now we have to guess. If you want to know more there are more of Jolyon’s drawings and a review of real attempts to map states of consciousness in my textbook Consciousness: An Introduction.