There is so much to say about this article — too much for one response, so I'd like to respond to just a few points.
First, the idea, or ideal, of enlightenment is a strange one and as I have written elsewhere, in my view it is at best a metaphor. Because the self is an illusion then it cannot be enlightened; and because what is behind or underlying the self is full consciousness as a whole, dynamic, and complex existence, then it cannot be enlightened either.
Next, I cannot speak for Buddhism. I am not a Buddhist though I have studied it a bit, but my interest is more related to the metaphor of the Buddha and his life as a myth. I have heard several Buddhists, including Robert Thurman, speak about enlightenment and it is described in ways that I feel describe an ideal of a superhuman who has abilities that, to me, are unrealistic. There is more I can say about this, which I did in the dialog we shared, so I'll leave it at that.
Next, based on my own experiences I'll comment on a few things you wrote, starting with “the content of near-death experiences might be determined largely by cultural upbringing which shapes the person’s anticipations.” It seems evident to me that the psychological conditioning that creates the self as a personal identity system, is never fully extinguished or dissolved. For people who have not actively delved into (meditated or enquired into) this sense of self it is unlikely that it will even partially move out of the way long enough to experience a full clarity of the mind without thought. It may in rare circumstances, but the experience is likely to be misunderstood or even overlooked. Therefore, during various altered states of reality I feel that people do retain their sense of self, including in NDEs, out of body experiences, dreams, plant hallucinatory experiences, and meditations.
In the case of complete disappearance of the self, the body, the world, and the awareness, as I have experienced many times, there is nothing going on at all, because without awareness nothing can be known, felt or experienced. It is only when I have regained awareness and the process reversed that I could speak about it, but I cannot describe the essence of the experience in the same way that a person cannot describe what it's like to be in deep, dreamless sleep or a coma.
Next, you wrote: “… the cosmos’s indifference and impersonality that run contrary to joy, awe, and contentment. …” The experience of no-thought and complete mental clarity, according to my own experience, is without any emotion at all; it is unalloyed. There is no joy, awe, contentment, sadness, depression, shame, anger, or any other emotion or feeling; there is only an unalloyed observation devoid of thought. The experience of the world is greatly heightened and all the senses are acute, but the sense of self is not present. This is a common state of some (I have no idea how many) people who have had thought shut off as if by flicking a switch without effort or desire. Without the self there are no feelings or mentations attached to this state.
Next, you wrote: “…Yet however enlightened the mindset, the sage must still work with the human brain that evolved to be self-centered…” This seems to move into a couple of disciplines beyond spirituality. Neuroscientists studying the brains of longtime Buddhist meditators such as Matthieu Ricard have discovered that the brain actually changes plasticity, so I would say that the brain they are "working with" is not the same as other people's brains, including one that has evolved to be a certain way.
Next, you wrote: “…you can train your mind to enter one or another state…” In my own experience this is true of some states, such as the out of body state or some meditative states, especially ones using visualizations, but it is a misunderstanding when it comes to the idea or ideal of enlightenment. The mind is not trained at all. In fact, it's just the opposite. Psychology retrains the already trained mind, but I have found that letting go of all training, conditioning, judgments, etc., brings about a clarity of the mind enough to change one's worldview. This cannot be practiced or attained or obtained in any logical process. To know what we are and to find what underlies thought, the self, and all else is a process of elimination that does not involve thinking, learning, praying, or effort. Since the self is made of thought, when thought disappears so does the self. This is achieved by persistently turning the attention away from the object and back to the subject until one can go deep enough so that the self is dissolved.
Lastly, it is my experience that the logical, intellectual mind of the self cannot grasp what it implies and what it is like to realize a thought-free, clear, empty mind. It's not possible, because the self that is making the assessment is a self that has been conditioned to see things from a certain subject-object paradigm. So it is a case of a self trying to see something beyond itself, which is not possible. To know what it is like to have complete clarity of the mind devoid of the self it takes being in that state. Otherwise we have a situation of a perception being made through the lens of duality and the conditioned mind trying to know what it is like not to be conditioned.
I cannot speak for Buddhism or any other person, but only by way of my own experience after decades of enquiring into the self. This had nothing at all to do with practice, learning, rituals, prayers, ideas, beliefs, imagination, or any process involving thought or effort. Ultimately it has to do with letting go of what you believe you are.
